Index: src/main/java/com/xpn/xwiki/user/impl/xwiki/AppServerTrustedKerberosAuthServiceImpl.java
===================================================================
--- src/main/java/com/xpn/xwiki/user/impl/xwiki/AppServerTrustedKerberosAuthServiceImpl.java	(revision 0)
+++ src/main/java/com/xpn/xwiki/user/impl/xwiki/AppServerTrustedKerberosAuthServiceImpl.java	(revision 0)
@@ -0,0 +1,117 @@
+/*
+ * See the NOTICE file distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This 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 software 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 software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package com.xpn.xwiki.user.impl.xwiki;
+
+import java.text.MessageFormat;
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import com.xpn.xwiki.XWikiContext;
+import com.xpn.xwiki.XWikiException;
+import com.xpn.xwiki.user.api.XWikiUser;
+
+/**
+ * Implements a authentication mechanism which is trusting the App Server authentication. If it fails it falls back to
+ * the standard XWiki authentication
+ */
+public class AppServerTrustedKerberosAuthServiceImpl extends XWikiAuthServiceImpl
+{
+
+    private static final Log LOG = LogFactory.getLog(AppServerTrustedKerberosAuthServiceImpl.class);
+
+    /**
+     * @see com.xpn.xwiki.user.impl.xwiki.XWikiAuthServiceImpl#checkAuth(com.xpn.xwiki.XWikiContext)
+     */
+    @Override
+    public XWikiUser checkAuth(XWikiContext context) throws XWikiException
+    {
+        String user = context.getRequest().getRemoteUser();
+        
+        LOG.debug(MessageFormat.format("Checking auth for remote user {0}", user));
+        
+        if ((user == null) || user.equals(""))
+            return super.checkAuth(context);
+        else {
+            if (user.contains("\\"))
+                if (user.lastIndexOf("\\") + 1 < user.length())
+                    user = user.substring(user.lastIndexOf("\\") + 1);
+                else {
+                    user = "";
+                    return super.checkAuth(context);
+                }
+
+            if (user.contains("@")) {
+                user = StringUtils.substringBeforeLast(user, "@");
+            }
+
+            LOG.debug("Launching create user for " + user);
+
+            user = createUser(user, context);
+
+            LOG.debug("Create user done for " + user);
+
+            user = "XWiki." + user;
+        }
+        context.setUser(user);
+
+        return new XWikiUser(user);
+    }
+
+    /**
+     * @see com.xpn.xwiki.user.impl.xwiki.XWikiAuthServiceImpl#checkAuth(java.lang.String, java.lang.String,
+     *      java.lang.String, com.xpn.xwiki.XWikiContext)
+     */
+    @Override
+    public XWikiUser checkAuth(String username, String password, String rememberme, XWikiContext context)
+        throws XWikiException
+    {
+        
+        String user = context.getRequest().getRemoteUser();
+        
+        LOG.debug(MessageFormat.format("Checking auth for remote user {0}", user));
+        
+        if ((user == null) || user.equals("")) {
+            return super.checkAuth(username, password, rememberme, context);
+        } else {
+            if (user.contains("\\"))
+
+                user = StringUtils.substringBeforeLast(user, "\\");
+
+            else {
+                user = "";
+                return super.checkAuth(username, password, rememberme, context);
+            }
+
+            if (user.contains("@")) {
+                user = StringUtils.substringBeforeLast(user, "@");
+            }
+
+            user = createUser(user, context);
+
+            user = "XWiki." + user;
+        }
+        context.setUser(user);
+
+        return new XWikiUser(user);
+    }
+    
+}
Index: src/main/java/com/xpn/xwiki/user/impl/xwiki/XWikiAuthServiceImpl.java
===================================================================
--- src/main/java/com/xpn/xwiki/user/impl/xwiki/XWikiAuthServiceImpl.java	(revision 33843)
+++ src/main/java/com/xpn/xwiki/user/impl/xwiki/XWikiAuthServiceImpl.java	(working copy)
@@ -605,7 +605,7 @@
         return param;
     }
 
-    protected void createUser(String user, XWikiContext context) throws XWikiException
+    protected String createUser(String user, XWikiContext context) throws XWikiException
     {
         String createuser = getParam("auth_createuser", context);
 
@@ -648,7 +648,11 @@
                     LOG.debug("User page already exists for user " + user);
                 }
             }
+
+            return wikiname;
         }
+
+        return user;
     }
 
     /**