diff --git a/ccm-core/src/main/java/org/libreccm/core/AbstractEntityRepository.java b/ccm-core/src/main/java/org/libreccm/core/AbstractEntityRepository.java
index b61e05236..888474f6b 100644
--- a/ccm-core/src/main/java/org/libreccm/core/AbstractEntityRepository.java
+++ b/ccm-core/src/main/java/org/libreccm/core/AbstractEntityRepository.java
@@ -45,10 +45,6 @@ public abstract class AbstractEntityRepository<K, E> {
      */
     @Inject
     private transient EntityManager entityManager;
-    
-    @Inject
-    @HibernateValidator
-    private Validator validator;
 
     /**
      * Getter method for retrieving the injected {@link EntityManager}.
diff --git a/ccm-core/src/main/java/org/libreccm/core/CcmObjectRepository.java b/ccm-core/src/main/java/org/libreccm/core/CcmObjectRepository.java
index 52885c1a4..beca673d7 100644
--- a/ccm-core/src/main/java/org/libreccm/core/CcmObjectRepository.java
+++ b/ccm-core/src/main/java/org/libreccm/core/CcmObjectRepository.java
@@ -37,7 +37,7 @@ public class CcmObjectRepository extends AbstractEntityRepository<Long, CcmObjec
     @Override
     public boolean isNew(final CcmObject entity) {
         if (entity == null) {
-            throw new IllegalArgumentException("Entity can't be null");
+            throw new IllegalArgumentException("Can't save null.");
         }
         return entity.getObjectId() == 0;
     }
diff --git a/ccm-core/src/main/java/org/libreccm/core/MultipleMatchingUserException.java b/ccm-core/src/main/java/org/libreccm/core/MultipleMatchingUserException.java
new file mode 100644
index 000000000..24864f05f
--- /dev/null
+++ b/ccm-core/src/main/java/org/libreccm/core/MultipleMatchingUserException.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2015 LibreCCM Foundation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301  USA
+ */
+package org.libreccm.core;
+
+/**
+ *
+ * @author <a href="mailto:jens.pelzetter@googlemail.com">Jens Pelzetter</a>
+ */
+class MultipleMatchingUserException extends RuntimeException {
+    private static final long serialVersionUID = 100237510055701060L;
+    
+    public MultipleMatchingUserException() {
+        super();
+    }
+    
+    public MultipleMatchingUserException(final String msg) {
+        super(msg);
+    }
+    
+    public MultipleMatchingUserException(final Exception cause) {
+        super(cause);
+    }
+    
+    public MultipleMatchingUserException(final String msg,
+                                         final Exception cause) {
+        super(msg, cause);
+    }
+    
+}
diff --git a/ccm-core/src/main/java/org/libreccm/core/Subject.java b/ccm-core/src/main/java/org/libreccm/core/Subject.java
index 578e5b0c1..d484d3a55 100644
--- a/ccm-core/src/main/java/org/libreccm/core/Subject.java
+++ b/ccm-core/src/main/java/org/libreccm/core/Subject.java
@@ -31,6 +31,7 @@ import javax.persistence.CollectionTable;
 import javax.persistence.Column;
 import javax.persistence.ElementCollection;
 import javax.persistence.Entity;
+import javax.persistence.FetchType;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
 import javax.persistence.Id;
@@ -62,7 +63,7 @@ public class Subject implements Serializable {
     @GeneratedValue(strategy = GenerationType.AUTO)
     private long subjectId;
 
-    @ElementCollection
+    @ElementCollection(fetch = FetchType.EAGER)
     @CollectionTable(name = "subject_email_addresses",
                      joinColumns = {
                          @JoinColumn(name = "subject_id")})
@@ -81,6 +82,7 @@ public class Subject implements Serializable {
     public Subject() {
         super();
 
+        emailAddresses = new ArrayList<>();
         grantedPermissions = new ArrayList<>();
     }
 
@@ -155,7 +157,7 @@ public class Subject implements Serializable {
             return false;
         }
 
-        return (subjectId == other.getSubjectId());
+        return subjectId == other.getSubjectId();
     }
 
     public boolean canEqual(final Object obj) {
diff --git a/ccm-core/src/main/java/org/libreccm/core/User.java b/ccm-core/src/main/java/org/libreccm/core/User.java
index 8c633410d..bcd64b0f8 100644
--- a/ccm-core/src/main/java/org/libreccm/core/User.java
+++ b/ccm-core/src/main/java/org/libreccm/core/User.java
@@ -141,6 +141,7 @@ public class User extends Subject implements Serializable {
      * the next login.
      */
     @Column(name = "password_reset_required")
+    @SuppressWarnings("PMD.LongVariable") //Name is fine...
     private boolean passwordResetRequired;
 
     /**
@@ -232,6 +233,7 @@ public class User extends Subject implements Serializable {
         return passwordResetRequired;
     }
 
+    @SuppressWarnings("PMD.LongVariable")
     public void setPasswordResetRequired(final boolean passwordResetRequired) {
         this.passwordResetRequired = passwordResetRequired;
     }
diff --git a/ccm-core/src/main/java/org/libreccm/core/UserRepository.java b/ccm-core/src/main/java/org/libreccm/core/UserRepository.java
index 8fefffb5e..c14646039 100644
--- a/ccm-core/src/main/java/org/libreccm/core/UserRepository.java
+++ b/ccm-core/src/main/java/org/libreccm/core/UserRepository.java
@@ -37,6 +37,9 @@ public class UserRepository extends AbstractEntityRepository<Long, User> {
 
     @Override
     public boolean isNew(final User entity) {
+        if (entity == null) {
+            throw new IllegalArgumentException("Can't save null.");
+        }
         return entity.getSubjectId() == 0;
     }
 
@@ -47,16 +50,14 @@ public class UserRepository extends AbstractEntityRepository<Long, User> {
 
         final List<User> result = query.getResultList();
 
+        //Check if result list is empty and if not return the first element.
+        //If their ist a result than there can only be one because the 
+        //screen_name column has a unique constraint.
         if (result.isEmpty()) {
             return null;
-        } else if (result.size() == 1) {
+        } else  {
             return result.get(0);
-        } else {
-            throw new MultipleMatchingUserException(String.format(
-                "Found multipe users identified by screen name '%s'. "
-                    + "Check your database.",
-                screenname));
-        }
+        } 
     }
 
     public User findByEmailAddress(final String emailAddress) {
@@ -78,14 +79,5 @@ public class UserRepository extends AbstractEntityRepository<Long, User> {
         }
     }
 
-    private class MultipleMatchingUserException extends RuntimeException {
-
-        private static final long serialVersionUID = 100237510055701060L;
-
-        public MultipleMatchingUserException(final String message) {
-            super(message);
-        }
-
-    }
 
 }
diff --git a/ccm-core/src/site/site.xml b/ccm-core/src/site/site.xml
index 3c6e867a3..8b30116e5 100644
--- a/ccm-core/src/site/site.xml
+++ b/ccm-core/src/site/site.xml
@@ -8,6 +8,7 @@
         <menu name="Overview">
             <item name="The Core module" href="index.html"/>
         </menu>
+        
         <menu ref="reports"/>
     </body>
     <!--<skin>
diff --git a/ccm-core/src/test/java/org/libreccm/core/UserRepositoryTest.java b/ccm-core/src/test/java/org/libreccm/core/UserRepositoryTest.java
index 49d9afda3..20c03efe7 100644
--- a/ccm-core/src/test/java/org/libreccm/core/UserRepositoryTest.java
+++ b/ccm-core/src/test/java/org/libreccm/core/UserRepositoryTest.java
@@ -19,17 +19,21 @@
 package org.libreccm.core;
 
 import java.io.File;
+
 import javax.inject.Inject;
 import javax.persistence.EntityManager;
 import javax.persistence.PersistenceContext;
+
 import org.junit.Test;
 
 import static org.hamcrest.Matchers.*;
 
 import org.jboss.arquillian.container.test.api.Deployment;
+import org.jboss.arquillian.container.test.api.ShouldThrowException;
 import org.jboss.arquillian.junit.Arquillian;
 import org.jboss.arquillian.junit.InSequence;
 import org.jboss.arquillian.persistence.PersistenceTest;
+import org.jboss.arquillian.persistence.ShouldMatchDataSet;
 import org.jboss.arquillian.persistence.UsingDataSet;
 import org.jboss.arquillian.transaction.api.annotation.TransactionMode;
 import org.jboss.arquillian.transaction.api.annotation.Transactional;
@@ -49,6 +53,10 @@ import org.junit.experimental.categories.Category;
 import org.junit.runner.RunWith;
 import org.libreccm.tests.categories.IntegrationTest;
 
+import java.util.List;
+
+import javax.persistence.Query;
+
 /**
  *
  * @author <a href="mailto:jens.pelzetter@googlemail.com">Jens Pelzetter</a>
@@ -92,10 +100,10 @@ public class UserRepositoryTest {
     @Deployment
     public static WebArchive createDeployment() {
         final PomEquippedResolveStage pom = Maven
-                .resolver()
-                .loadPomFromFile("pom.xml");
+            .resolver()
+            .loadPomFromFile("pom.xml");
         final PomEquippedResolveStage dependencies = pom.
-                importCompileAndRuntimeDependencies();
+            importCompileAndRuntimeDependencies();
         final File[] libs = dependencies.resolve().withTransitivity().asFile();
 
         for (File lib : libs) {
@@ -104,26 +112,26 @@ public class UserRepositoryTest {
         }
 
         return ShrinkWrap
-                .create(WebArchive.class,
-                        "LibreCCM-org.libreccm.core.UserRepositoryTest.war")
-                .addPackage(User.class.getPackage())
-                .addPackage(org.libreccm.web.Application.class.getPackage())
-                .addPackage(org.libreccm.categorization.Category.class.
-                        getPackage())
-                .addPackage(org.libreccm.l10n.LocalizedString.class.getPackage()).
-                addPackage(org.libreccm.jpa.EntityManagerProducer.class
-                        .getPackage())
-                .addPackage(org.libreccm.jpa.utils.MimeTypeConverter.class
-                        .getPackage())
-                .addPackage(org.libreccm.testutils.EqualsVerifier.class.
-                        getPackage())
-                .addPackage(org.libreccm.tests.categories.IntegrationTest.class
-                        .getPackage())
-                .addAsLibraries(libs)
-                .addAsResource("test-persistence.xml",
-                               "META-INF/persistence.xml")
-                .addAsWebInfResource("test-web.xml", "WEB-INF/web.xml")
-                .addAsWebInfResource(EmptyAsset.INSTANCE, "WEB-INF/beans.xml");
+            .create(WebArchive.class,
+                    "LibreCCM-org.libreccm.core.UserRepositoryTest.war")
+            .addPackage(User.class.getPackage())
+            .addPackage(org.libreccm.web.Application.class.getPackage())
+            .addPackage(org.libreccm.categorization.Category.class.
+                getPackage())
+            .addPackage(org.libreccm.l10n.LocalizedString.class.getPackage()).
+            addPackage(org.libreccm.jpa.EntityManagerProducer.class
+                .getPackage())
+            .addPackage(org.libreccm.jpa.utils.MimeTypeConverter.class
+                .getPackage())
+            .addPackage(org.libreccm.testutils.EqualsVerifier.class.
+                getPackage())
+            .addPackage(org.libreccm.tests.categories.IntegrationTest.class
+                .getPackage())
+            .addAsLibraries(libs)
+            .addAsResource("test-persistence.xml",
+                           "META-INF/persistence.xml")
+            .addAsWebInfResource("test-web.xml", "WEB-INF/web.xml")
+            .addAsWebInfResource(EmptyAsset.INSTANCE, "WEB-INF/beans.xml");
 
     }
 
@@ -137,11 +145,11 @@ public class UserRepositoryTest {
         assertThat(entityManager, is(not(nullValue())));
     }
 
-    private void checkUsers(final User jdoe, 
-                            final User mmuster, 
-                            final User joe, 
+    private void checkUsers(final User jdoe,
+                            final User mmuster,
+                            final User joe,
                             final User nobody) {
-                assertThat(jdoe, is(not(nullValue())));
+        assertThat(jdoe, is(not(nullValue())));
         assertThat(jdoe.getSubjectId(), is(-10L));
         assertThat(jdoe.getScreenName(), is(JDOE));
         assertThat(jdoe.getName().getFamilyName(), is(equalTo("Doe")));
@@ -176,24 +184,23 @@ public class UserRepositoryTest {
         assertThat(nobody, is(nullValue()));
 
     }
-    
+
     @Test
     @UsingDataSet(
-            "datasets/org/libreccm/core/UserRepositoryTest/data.json")
-    @InSequence(10)
+        "datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @InSequence(100)
     public void findUserById() {
         final User jdoe = userRepository.findById(-10L);
         final User mmuster = userRepository.findById(-20L);
         final User joe = userRepository.findById(-30L);
         final User nobody = userRepository.findById(-999L);
-        
+
         checkUsers(jdoe, mmuster, joe, nobody);
     }
-    
+
     @Test
-    @UsingDataSet(
-            "datasets/org/libreccm/core/UserRepositoryTest/data.json")
-    @InSequence(20)
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @InSequence(200)
     public void findUserByScreenName() {
         final User jdoe = userRepository.findByScreenName(JDOE);
         final User mmuster = userRepository.findByScreenName(MMUSTER);
@@ -201,94 +208,130 @@ public class UserRepositoryTest {
         final User nobody = userRepository.findByScreenName(NOBODY);
 
         checkUsers(jdoe, mmuster, joe, nobody);
-        
-//        assertThat(jdoe, is(not(nullValue())));
-//        assertThat(jdoe.getSubjectId(), is(-10L));
-//        assertThat(jdoe.getScreenName(), is(JDOE));
-//        assertThat(jdoe.getName().getFamilyName(), is(equalTo("Doe")));
-//        assertThat(jdoe.getName().getMiddleName(), is(nullValue()));
-//        assertThat(jdoe.getName().getGivenName(), is(equalTo("John")));
-//        assertThat(jdoe.getHashAlgorithm(), is("MD5"));
-//        assertThat(jdoe.getPassword(), is("604622dc8a888eb093454ebd77ca1675"));
-//        assertThat(jdoe.getSalt(), is("axg8ira8fa"));
-//
-//        assertThat(mmuster, is(not(nullValue())));
-//        assertThat(mmuster.getSubjectId(), is(-20L));
-//        assertThat(mmuster.getScreenName(), is(equalTo(MMUSTER)));
-//        assertThat(mmuster.getName().getFamilyName(), is(equalTo("Mustermann")));
-//        assertThat(mmuster.getName().getMiddleName(), is(nullValue()));
-//        assertThat(mmuster.getName().getGivenName(), is(equalTo("Max")));
-//        assertThat(mmuster.getHashAlgorithm(), is(equalTo("SHA-512")));
-//        assertThat(mmuster.getPassword(), is(equalTo(
-//                   "1c9626af429a6291766d15cbfb38689bd8d49450520765973de70aecaf644b7d4fda711266ba9ec8fb6df30c8ab391d40330829aa85adf371bcde6b4c9bc01e6")));
-//        assertThat(mmuster.getSalt(), is(equalTo("fjiajhigafgapoa")));
-//
-//        assertThat(joe, is(not(nullValue())));
-//        assertThat(joe.getSubjectId(), is(-30L));
-//        assertThat(joe.getScreenName(), is(equalTo(JOE)));
-//        assertThat(joe.getName().getFamilyName(), is(equalTo("Public")));
-//        assertThat(joe.getName().getMiddleName(), is(nullValue()));
-//        assertThat(joe.getName().getGivenName(), is(equalTo("Joe")));
-//        assertThat(joe.getHashAlgorithm(), is(equalTo("SHA-512")));
-//        assertThat(joe.getPassword(), is(equalTo(
-//                   "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975")));
-//        assertThat(joe.getSalt(), is(equalTo("axg8ira8fa")));
-//
-//        assertThat(nobody, is(nullValue()));
     }
 
     @Test
-    @UsingDataSet(
-            "datasets/org/libreccm/core/UserRepositoryTest/data.json")
-    @InSequence(30)
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @InSequence(300)
     public void findUserByEmail() {
-        final User jdoe = userRepository.findByEmailAddress("john.doe@example.com");
-        final User mmuster1 = userRepository.findByEmailAddress("max.mustermann@example.org");
-        final User mmuster2 = userRepository.findByEmailAddress("mm@example.com");
-        final User joe = userRepository.findByEmailAddress("joe.public@example.com");
-        final User nobody = userRepository.findByScreenName("nobody@example.org");
+        final User jdoe = userRepository.findByEmailAddress(
+            "john.doe@example.com");
+        final User mmuster1 = userRepository.findByEmailAddress(
+            "max.mustermann@example.org");
+        final User mmuster2 = userRepository
+            .findByEmailAddress("mm@example.com");
+        final User joe = userRepository.findByEmailAddress(
+            "joe.public@example.com");
+        final User nobody = userRepository
+            .findByEmailAddress("nobody@example.org");
 
         checkUsers(jdoe, mmuster1, joe, nobody);
-        
-        assertThat(mmuster2, is(equalTo(mmuster1)));
-        
-//        assertThat(jdoe, is(not(nullValue())));
-//        assertThat(jdoe.getSubjectId(), is(-10L));
-//        assertThat(jdoe.getScreenName(), is(JDOE));
-//        assertThat(jdoe.getName().getFamilyName(), is(equalTo("Doe")));
-//        assertThat(jdoe.getName().getMiddleName(), is(nullValue()));
-//        assertThat(jdoe.getName().getGivenName(), is(equalTo("John")));
-//        assertThat(jdoe.getHashAlgorithm(), is("MD5"));
-//        assertThat(jdoe.getPassword(), is("604622dc8a888eb093454ebd77ca1675"));
-//        assertThat(jdoe.getSalt(), is("axg8ira8fa"));
-//
-//        assertThat(mmuster1, is(not(nullValue())));
-//        assertThat(mmuster1.getSubjectId(), is(-20L));
-//        assertThat(mmuster1.getScreenName(), is(equalTo(MMUSTER)));
-//        assertThat(mmuster1.getName().getFamilyName(), is(equalTo("Mustermann")));
-//        assertThat(mmuster1.getName().getMiddleName(), is(nullValue()));
-//        assertThat(mmuster1.getName().getGivenName(), is(equalTo("Max")));
-//        assertThat(mmuster1.getHashAlgorithm(), is(equalTo("SHA-512")));
-//        assertThat(mmuster1.getPassword(), is(equalTo(
-//                   "1c9626af429a6291766d15cbfb38689bd8d49450520765973de70aecaf644b7d4fda711266ba9ec8fb6df30c8ab391d40330829aa85adf371bcde6b4c9bc01e6")));
-//        assertThat(mmuster1.getSalt(), is(equalTo("fjiajhigafgapoa")));
-//
-//        assertThat(mmuster2, is(equalTo(mmuster1)));
-//        //assertThat(mmuster2.equals(mmuster1), is(true));
-//        
-//        assertThat(joe, is(not(nullValue())));
-//        assertThat(joe.getSubjectId(), is(-30L));
-//        assertThat(joe.getScreenName(), is(equalTo(JOE)));
-//        assertThat(joe.getName().getFamilyName(), is(equalTo("Public")));
-//        assertThat(joe.getName().getMiddleName(), is(nullValue()));
-//        assertThat(joe.getName().getGivenName(), is(equalTo("Joe")));
-//        assertThat(joe.getHashAlgorithm(), is(equalTo("SHA-512")));
-//        assertThat(joe.getPassword(), is(equalTo(
-//                   "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975")));
-//        assertThat(joe.getSalt(), is(equalTo("axg8ira8fa")));
-//
-//        assertThat(nobody, is(nullValue()));
 
+        assertThat(mmuster2, is(equalTo(mmuster1)));
+    }
+
+    @Test(expected = MultipleMatchingUserException.class)
+    @ShouldThrowException(MultipleMatchingUserException.class)
+    @UsingDataSet(
+        "datasets/org/libreccm/core/UserRepositoryTest/data-email-duplicate.json")
+    @InSequence(350)
+    public void findByEmailAddressDuplicate() {
+        userRepository.findByEmailAddress("max.mustermann@example.org");
+    }
+
+    @Test
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @InSequence(400)
+    public void findAllUsers() {
+        final List<User> users = userRepository.findAll();
+
+        assertThat(users.size(), is(3));
+    }
+
+    @Test
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @ShouldMatchDataSet(value
+                            = "datasets/org/libreccm/core/UserRepositoryTest/after-save-new.json",
+                        excludeColumns = {"subject_id"})
+    @InSequence(500)
+    public void saveNewUser() {
+        final User user = new User();
+
+        final PersonName personName = new PersonName();
+        personName.setGivenName("Jane");
+        personName.setMiddleName("Anna");
+        personName.setFamilyName("Doe");
+        personName.setTitlePre("Dr.");
+        user.setName(personName);
+
+        final EmailAddress emailAddress = new EmailAddress();
+        emailAddress.setAddress("jane.doe@example.org");
+        emailAddress.setBouncing(false);
+        emailAddress.setVerified(false);
+        user.addEmailAddress(emailAddress);
+
+        user.setScreenName("jane");
+        user.setPassword(
+            "32d2a830fb03f201bda975ae70a62c207716705a049e054cf6701de1cec546d3a9e03a094be2e98e4d125af996ebbfa5a7754754a1e9d2fe063a0d9921cb201d");
+        user.setHashAlgorithm("SHA-512");
+        user.setSalt("maifgaoapafga9");
+        user.setPasswordResetRequired(false);
+
+        userRepository.save(user);
+    }
+
+    @Test
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @ShouldMatchDataSet(value
+                            = "datasets/org/libreccm/core/UserRepositoryTest/after-save-changed.json",
+                        excludeColumns = {"subject_id"})
+    @InSequence(600)
+    public void saveChangedUser() {
+        final User user = userRepository.findById(-10L);
+
+        user.getName().setTitlePre("Dr.");
+
+        user.setHashAlgorithm("SHA-512");
+        user.setPassword(
+            "19f69a0f8eab3e6124d1b40ca2ae1fc3ece311cf86dde4e9560521e881fb8f063817cf1da1234144825f40fc9b9acd1563cafcb35fb8533544a1b6c3615160e3");
+        user.setSalt("fafjiaddfja0a");
+
+        final EmailAddress emailAddress = new EmailAddress();
+        emailAddress.setAddress("jd@example.com");
+        emailAddress.setBouncing(false);
+        emailAddress.setVerified(true);
+        user.addEmailAddress(emailAddress);
+
+        final EmailAddress old = user.getEmailAddresses().get(0);
+        user.removeEmailAddress(old);
+
+        userRepository.save(user);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    @ShouldThrowException(IllegalArgumentException.class)
+    @InSequence(700)
+    public void saveNullValue() {
+        userRepository.save(null);
+    }
+
+    @Test
+    @UsingDataSet("datasets/org/libreccm/core/UserRepositoryTest/data.json")
+    @ShouldMatchDataSet(value
+                            = "datasets/org/libreccm/core/UserRepositoryTest/after-delete.json",
+                        excludeColumns = {"subject_id"})
+    @InSequence(800)
+    public void deleteUser() {
+        final User user = userRepository.findByScreenName("mmuster");
+
+        userRepository.delete(user);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    @ShouldThrowException(IllegalArgumentException.class)
+    @InSequence(900)
+    public void deleteNullValue() {
+        userRepository.delete(null);
     }
 
 }
diff --git a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-delete.json b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-delete.json
index f2105ff0b..2d1ac388b 100644
--- a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-delete.json
+++ b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-delete.json
@@ -30,16 +30,10 @@
                     "hash_algorithm": "MD5",
                     "family_name": "Doe",
                     "given_name": "John",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
                     "password": "604622dc8a888eb093454ebd77ca1675",
-                    "password_answer": null,
-                    "password_question": null,
                     "password_reset_required": false,
                     "salt": "axg8ira8fa",
                     "screen_name": "jdoe",
-                    "sso_login": null,
                     "subject_id": -10
                 },
                 {
@@ -47,16 +41,10 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Public",
                     "given_name": "Joe",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
-                    "password": "e9db883a56149f7521a00713c4d7b0c967ae42cc3f0dfcf96ccd0180c498abf57209a90db9cb5df3a7d23d4111e87578e09ea610e9c1d95c4695710e28c5ab02",
-                    "password_answer": null,
-                    "password_question": null,
+                    "password": "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975",
                     "password_reset_required": false,
                     "salt": "axg8ira8fa",
                     "screen_name": "joe",
-                    "sso_login": null,
                     "subject_id": -30
                 }
             ]
diff --git a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-changed.json b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-changed.json
index 1a48c5dd4..cedf058d2 100644
--- a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-changed.json
+++ b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-changed.json
@@ -15,7 +15,7 @@
             [
                 {
                     "subject_id": -10,
-                    "email_address": "john.doe@example.com",
+                    "email_address": "jd@example.com",
                     "bouncing": false,
                     "verified": true
                 },
@@ -45,16 +45,11 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Doe",
                     "given_name": "John",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
+                    "title_pre": "Dr.",
                     "password": "19f69a0f8eab3e6124d1b40ca2ae1fc3ece311cf86dde4e9560521e881fb8f063817cf1da1234144825f40fc9b9acd1563cafcb35fb8533544a1b6c3615160e3",
-                    "password_answer": null,
-                    "password_question": null,
                     "password_reset_required": false,
                     "salt": "fafjiaddfja0a",
                     "screen_name": "jdoe",
-                    "sso_login": null,
                     "subject_id": -10
                 },
                 {
@@ -62,16 +57,10 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Mustermann",
                     "given_name": "Max",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
-                    "password": "3428dfa9bb199f3372eb73c5feb038aef5bcbbfd4fada24c44026a25c883a9f2af8b84410a3b2684430d359f78400ad92ff8c71634f2c9bf437f0cd56c5d90c3",
-                    "password_answer": null,
-                    "password_question": null,
+                    "password": "1c9626af429a6291766d15cbfb38689bd8d49450520765973de70aecaf644b7d4fda711266ba9ec8fb6df30c8ab391d40330829aa85adf371bcde6b4c9bc01e6",
                     "password_reset_required": false,
                     "salt": "fjiajhigafgapoa",
                     "screen_name": "mmuster",
-                    "sso_login": null,
                     "subject_id": -20
                 },
                 {
@@ -79,16 +68,10 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Public",
                     "given_name": "Joe",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
-                    "password": "e9db883a56149f7521a00713c4d7b0c967ae42cc3f0dfcf96ccd0180c498abf57209a90db9cb5df3a7d23d4111e87578e09ea610e9c1d95c4695710e28c5ab02",
-                    "password_answer": null,
-                    "password_question": null,
+                    "password": "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975",
                     "password_reset_required": false,
                     "salt": "axg8ira8fa",
                     "screen_name": "joe",
-                    "sso_login": null,
                     "subject_id": -30
                 }
             ]
diff --git a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-new.json b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-new.json
index 92977ad05..7ab220873 100644
--- a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-new.json
+++ b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/after-save-new.json
@@ -54,16 +54,10 @@
                     "hash_algorithm": "MD5",
                     "family_name": "Doe",
                     "given_name": "John",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
                     "password": "604622dc8a888eb093454ebd77ca1675",
-                    "password_answer": null,
-                    "password_question": null,
                     "password_reset_required": false,
                     "salt": "axg8ira8fa",
                     "screen_name": "jdoe",
-                    "sso_login": null,
                     "subject_id": -10
                 },
                 {
@@ -71,16 +65,10 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Mustermann",
                     "given_name": "Max",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
-                    "password": "3428dfa9bb199f3372eb73c5feb038aef5bcbbfd4fada24c44026a25c883a9f2af8b84410a3b2684430d359f78400ad92ff8c71634f2c9bf437f0cd56c5d90c3",
-                    "password_answer": null,
-                    "password_question": null,
+                    "password": "1c9626af429a6291766d15cbfb38689bd8d49450520765973de70aecaf644b7d4fda711266ba9ec8fb6df30c8ab391d40330829aa85adf371bcde6b4c9bc01e6",
                     "password_reset_required": false,
                     "salt": "fjiajhigafgapoa",
                     "screen_name": "mmuster",
-                    "sso_login": null,
                     "subject_id": -20
                 },
                 {
@@ -88,16 +76,10 @@
                     "hash_algorithm": "SHA-512",
                     "family_name": "Public",
                     "given_name": "Joe",
-                    "middle_name": null,
-                    "title_post": null,
-                    "title_pre": null,
-                    "password": "e9db883a56149f7521a00713c4d7b0c967ae42cc3f0dfcf96ccd0180c498abf57209a90db9cb5df3a7d23d4111e87578e09ea610e9c1d95c4695710e28c5ab02",
-                    "password_answer": null,
-                    "password_question": null,
+                    "password": "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975",
                     "password_reset_required": false,
                     "salt": "axg8ira8fa",
                     "screen_name": "joe",
-                    "sso_login": null,
                     "subject_id": -30
                 },
                 {
@@ -106,15 +88,11 @@
                     "family_name": "Doe",
                     "given_name": "Jane",
                     "middle_name": "Anna",
-                    "title_post": null,
                     "title_pre": "Dr.",
                     "password": "32d2a830fb03f201bda975ae70a62c207716705a049e054cf6701de1cec546d3a9e03a094be2e98e4d125af996ebbfa5a7754754a1e9d2fe063a0d9921cb201d",
-                    "password_answer": null,
-                    "password_question": null,
                     "password_reset_required": false,
                     "salt": "maifgaoapafga9",
                     "screen_name": "jane",
-                    "sso_login": null,
                     "subject_id": -40
                 }
             ]
diff --git a/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/data-email-duplicate.json b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/data-email-duplicate.json
new file mode 100644
index 000000000..57c37343a
--- /dev/null
+++ b/ccm-core/src/test/resources/datasets/org/libreccm/core/UserRepositoryTest/data-email-duplicate.json
@@ -0,0 +1,77 @@
+{
+    "subjects":
+            [
+                {
+                    "subject_id": -10
+                },
+                {
+                    "subject_id": -20
+                },
+                {
+                    "subject_id": -30
+                }
+            ],
+    "subject_email_addresses":
+            [
+                {
+                    "subject_id": -10,
+                    "email_address": "john.doe@example.com",
+                    "bouncing": false,
+                    "verified": true
+                },
+                {
+                    "subject_id": -20,
+                    "email_address": "max.mustermann@example.org",
+                    "bouncing": false,
+                    "verified": true
+                },
+                {
+                    "subject_id": -20,
+                    "email_address": "mm@example.com",
+                    "bouncing": false,
+                    "verified": true
+                },
+                {
+                    "subject_id": -30,
+                    "email_address": "max.mustermann@example.org",
+                    "bouncing": true,
+                    "verified": false
+                }
+            ],
+    "ccm_users":
+            [
+                {
+                    "banned": false,
+                    "hash_algorithm": "MD5",
+                    "family_name": "Doe",
+                    "given_name": "John",
+                    "password": "604622dc8a888eb093454ebd77ca1675",
+                    "password_reset_required": false,
+                    "salt": "axg8ira8fa",
+                    "screen_name": "jdoe",
+                    "subject_id": -10
+                },
+                {
+                    "banned": false,
+                    "hash_algorithm": "SHA-512",
+                    "family_name": "Mustermann",
+                    "given_name": "Max",
+                    "password": "1c9626af429a6291766d15cbfb38689bd8d49450520765973de70aecaf644b7d4fda711266ba9ec8fb6df30c8ab391d40330829aa85adf371bcde6b4c9bc01e6",
+                    "password_reset_required": false,
+                    "salt": "fjiajhigafgapoa",
+                    "screen_name": "mmuster",
+                    "subject_id": -20
+                },
+                {
+                    "banned": false,
+                    "hash_algorithm": "SHA-512",
+                    "family_name": "Public",
+                    "given_name": "Joe",
+                    "password": "4e39eba7f2927182a532cd8700bf251e58d4b0359fbb832e6af21db7501d7a49e6d8b950e0d4b15b1841af0f786c8edaa0c09ef7f474804254f7e895969d2975",
+                    "password_reset_required": false,
+                    "salt": "axg8ira8fa",
+                    "screen_name": "joe",
+                    "subject_id": -30
+                }
+            ]
+}
\ No newline at end of file