diff --git a/scm-web-api/src/main/java/sonia/scm/web/plugin/SCMPlugin.java b/scm-web-api/src/main/java/sonia/scm/web/plugin/SCMPlugin.java
index f361b9300c..485c80d78f 100644
--- a/scm-web-api/src/main/java/sonia/scm/web/plugin/SCMPlugin.java
+++ b/scm-web-api/src/main/java/sonia/scm/web/plugin/SCMPlugin.java
@@ -29,15 +29,17 @@
  *
  */
 
+
+
 package sonia.scm.web.plugin;
 
 //~--- non-JDK imports --------------------------------------------------------
 
 import sonia.scm.repository.RepositoryHandler;
+import sonia.scm.user.UserHandler;
 
 //~--- JDK imports ------------------------------------------------------------
 
-import java.util.Collection;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -62,35 +64,8 @@ public class SCMPlugin
    */
   public SCMPlugin()
   {
-    handlers = new HashSet<Class<? extends RepositoryHandler>>();
-  }
-
-  //~--- methods --------------------------------------------------------------
-
-  /**
-   * Method description
-   *
-   *
-   * @param handlerClass
-   *
-   * @return
-   */
-  public boolean addHandler(Class<? extends RepositoryHandler> handlerClass)
-  {
-    return handlers.add(handlerClass);
-  }
-
-  /**
-   * Method description
-   *
-   *
-   * @param handlerClass
-   *
-   * @return
-   */
-  public boolean removeHandler(Class<? extends RepositoryHandler> handlerClass)
-  {
-    return handlers.remove(handlerClass);
+    repositoryHandlers = new HashSet<Class<? extends RepositoryHandler>>();
+    userHandlers = new HashSet<Class<? extends UserHandler>>();
   }
 
   //~--- get methods ----------------------------------------------------------
@@ -101,9 +76,9 @@ public class SCMPlugin
    *
    * @return
    */
-  public Collection<Class<? extends RepositoryHandler>> getHandlers()
+  public Set<Class<? extends RepositoryHandler>> getRepositoryHandlers()
   {
-    return handlers;
+    return repositoryHandlers;
   }
 
   /**
@@ -117,6 +92,17 @@ public class SCMPlugin
     return securityConfig;
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public Set<Class<? extends UserHandler>> getUserHandlers()
+  {
+    return userHandlers;
+  }
+
   /**
    * Method description
    *
@@ -130,6 +116,18 @@ public class SCMPlugin
 
   //~--- set methods ----------------------------------------------------------
 
+  /**
+   * Method description
+   *
+   *
+   * @param repositoryHandlers
+   */
+  public void setRepositoryHandlers(
+          Set<Class<? extends RepositoryHandler>> repositoryHandlers)
+  {
+    this.repositoryHandlers = repositoryHandlers;
+  }
+
   /**
    * Method description
    *
@@ -141,6 +139,17 @@ public class SCMPlugin
     this.securityConfig = securityConfig;
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @param userHandlers
+   */
+  public void setUserHandlers(Set<Class<? extends UserHandler>> userHandlers)
+  {
+    this.userHandlers = userHandlers;
+  }
+
   /**
    * Method description
    *
@@ -157,12 +166,17 @@ public class SCMPlugin
   /** Field description */
   @XmlElementWrapper(name = "repository-handlers")
   @XmlElement(name = "repository-handler")
-  private Set<Class<? extends RepositoryHandler>> handlers;
+  private Set<Class<? extends RepositoryHandler>> repositoryHandlers;
 
   /** Field description */
   @XmlElement(name = "security")
   private SecurityConfig securityConfig;
 
+  /** Field description */
+  @XmlElementWrapper(name = "user-handlers")
+  @XmlElement(name = "user-handler")
+  private Set<Class<? extends UserHandler>> userHandlers;
+
   /** Field description */
   @XmlElement(name = "web-plugin")
   private Class<? extends ScmWebPlugin> webPlugin;
diff --git a/scm-webapp/src/main/java/sonia/scm/ContextListener.java b/scm-webapp/src/main/java/sonia/scm/ContextListener.java
index c720c4d48b..e00ea55ae5 100644
--- a/scm-webapp/src/main/java/sonia/scm/ContextListener.java
+++ b/scm-webapp/src/main/java/sonia/scm/ContextListener.java
@@ -29,6 +29,8 @@
  *
  */
 
+
+
 package sonia.scm;
 
 //~--- non-JDK imports --------------------------------------------------------
@@ -42,6 +44,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import sonia.scm.repository.RepositoryManager;
+import sonia.scm.user.UserManager;
 import sonia.scm.util.Util;
 import sonia.scm.web.plugin.SCMPlugin;
 import sonia.scm.web.plugin.SCMPluginManager;
@@ -164,6 +167,9 @@ public class ContextListener extends GuiceServletContextListener
     // init RepositoryManager
     injector.getInstance(RepositoryManager.class).init(SCMContext.getContext());
 
+    // init UserManager
+    injector.getInstance(UserManager.class).init(SCMContext.getContext());
+
     // init Authenticator
     injector.getInstance(Authenticator.class).init(SCMContext.getContext());
 
diff --git a/scm-webapp/src/main/java/sonia/scm/ScmServletModule.java b/scm-webapp/src/main/java/sonia/scm/ScmServletModule.java
index 33fb0f8e18..2d05edaebc 100644
--- a/scm-webapp/src/main/java/sonia/scm/ScmServletModule.java
+++ b/scm-webapp/src/main/java/sonia/scm/ScmServletModule.java
@@ -29,6 +29,8 @@
  *
  */
 
+
+
 package sonia.scm;
 
 //~--- non-JDK imports --------------------------------------------------------
@@ -50,6 +52,10 @@ import sonia.scm.repository.RepositoryHandler;
 import sonia.scm.repository.RepositoryManager;
 import sonia.scm.security.EncryptionHandler;
 import sonia.scm.security.MessageDigestEncryptionHandler;
+import sonia.scm.user.BasicUserManager;
+import sonia.scm.user.UserHandler;
+import sonia.scm.user.UserManager;
+import sonia.scm.user.XmlUserHandler;
 import sonia.scm.util.DebugServlet;
 import sonia.scm.util.Util;
 import sonia.scm.web.plugin.SCMPlugin;
@@ -154,6 +160,7 @@ public class ScmServletModule extends ServletModule
     bind(RepositoryManager.class).annotatedWith(Undecorated.class).to(
         BasicRepositoryManager.class);
     bind(RepositoryManager.class).to(CacheRepositoryManagerDecorator.class);
+    bind(UserManager.class).to(BasicUserManager.class);
     bind(ScmWebPluginContext.class).toInstance(webPluginContext);
 
     /*
@@ -211,6 +218,28 @@ public class ScmServletModule extends ServletModule
     }
   }
 
+  /**
+   *  Method description
+   *
+   *
+   *  @param userHandlerBinder
+   *  @param handlerSet
+   */
+  private void bindUserHandlers(Multibinder<UserHandler> userHandlerBinder,
+                                Set<Class<? extends UserHandler>> handlerSet)
+  {
+    for (Class<? extends UserHandler> handlerClass : handlerSet)
+    {
+      if (logger.isInfoEnabled())
+      {
+        logger.info("load UserHandler {}", handlerClass.getName());
+      }
+
+      bind(handlerClass);
+      userHandlerBinder.addBinding().to(handlerClass);
+    }
+  }
+
   /**
    * Method description
    *
@@ -223,22 +252,42 @@ public class ScmServletModule extends ServletModule
 
     if (Util.isNotEmpty(pluginSet))
     {
+
+      // repository handlers
       Multibinder<RepositoryHandler> repositoryHandlerBinder =
         Multibinder.newSetBinder(binder(), RepositoryHandler.class);
-      Set<Class<? extends RepositoryHandler>> handlerSet =
+      Set<Class<? extends RepositoryHandler>> repositoryHandlerSet =
         new LinkedHashSet<Class<? extends RepositoryHandler>>();
+
+      // user handlers
+      Multibinder<UserHandler> userHandlerBinder =
+        Multibinder.newSetBinder(binder(), UserHandler.class);
+      Set<Class<? extends UserHandler>> userHandlerSet =
+        new LinkedHashSet<Class<? extends UserHandler>>();
+
+      userHandlerSet.add(XmlUserHandler.class);
+
+      // security stuff
       Class<? extends EncryptionHandler> encryptionHandler =
         MessageDigestEncryptionHandler.class;
       Class<? extends Authenticator> authenticator = XmlAuthenticator.class;
 
       for (SCMPlugin plugin : pluginSet)
       {
-        Collection<Class<? extends RepositoryHandler>> handlers =
-          plugin.getHandlers();
+        Collection<Class<? extends RepositoryHandler>> pluginRepositoryHandlers =
+          plugin.getRepositoryHandlers();
 
-        if (Util.isNotEmpty(handlers))
+        if (Util.isNotEmpty(pluginRepositoryHandlers))
         {
-          handlerSet.addAll(handlers);
+          repositoryHandlerSet.addAll(pluginRepositoryHandlers);
+        }
+
+        Collection<Class<? extends UserHandler>> pluginUserHandlers =
+          plugin.getUserHandlers();
+
+        if (Util.isNotEmpty(pluginUserHandlers))
+        {
+          userHandlerSet.addAll(pluginUserHandlers);
         }
 
         SecurityConfig securityConfig = plugin.getSecurityConfig();
@@ -265,7 +314,8 @@ public class ScmServletModule extends ServletModule
 
       bind(EncryptionHandler.class).to(encryptionHandler);
       bind(Authenticator.class).to(authenticator);
-      bindRepositoryHandlers(repositoryHandlerBinder, handlerSet);
+      bindRepositoryHandlers(repositoryHandlerBinder, repositoryHandlerSet);
+      bindUserHandlers(userHandlerBinder, userHandlerSet);
     }
   }