diff --git a/source/java/org/alfresco/repo/security/authentication/AuthenticationUtil.java b/source/java/org/alfresco/repo/security/authentication/AuthenticationUtil.java
new file mode 100644
index 0000000000..19a1897363
--- /dev/null
+++ b/source/java/org/alfresco/repo/security/authentication/AuthenticationUtil.java
@@ -0,0 +1,269 @@
+/*
+ * Copyright (C) 2005 Alfresco, Inc.
+ *
+ * Licensed under the Mozilla Public License version 1.1 
+ * with a permitted attribution clause. You may obtain a
+ * copy of the License at
+ *
+ *   http://www.alfresco.org/legal/license.txt
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific
+ * language governing permissions and limitations under the
+ * License.
+ */
+package org.alfresco.repo.security.authentication;
+
+import net.sf.acegisecurity.Authentication;
+import net.sf.acegisecurity.GrantedAuthority;
+import net.sf.acegisecurity.GrantedAuthorityImpl;
+import net.sf.acegisecurity.UserDetails;
+import net.sf.acegisecurity.context.Context;
+import net.sf.acegisecurity.context.ContextHolder;
+import net.sf.acegisecurity.context.security.SecureContext;
+import net.sf.acegisecurity.context.security.SecureContextImpl;
+import net.sf.acegisecurity.providers.UsernamePasswordAuthenticationToken;
+import net.sf.acegisecurity.providers.dao.User;
+
+import org.alfresco.service.cmr.security.PermissionService;
+
+public abstract class AuthenticationUtil
+{
+
+    public interface RunAsWork<Result>
+    {
+        /**
+         * Method containing the work to be done in the user transaction.
+         * 
+         * @return Return the result of the operation
+         */
+        Result doWork() throws Exception;
+    }
+
+    private static final String SYSTEM_USER_NAME = "System";
+
+    private AuthenticationUtil()
+    {
+        super();
+    }
+
+    public static Authentication setCurrentUser(String userName)
+    {
+        return setCurrentUser(userName, getDefaultUserDetails(userName));
+    }
+
+    /**
+     * Explicitly set the current user to be authenticated.
+     * 
+     * @param userName - String user id
+     * @param providedDetails - provided details for the user
+     * 
+     * @return Authentication
+     */
+    public static Authentication setCurrentUser(String userName, UserDetails providedDetails)
+            throws AuthenticationException
+    {
+        if (userName == null)
+        {
+            throw new AuthenticationException("Null user name");
+        }
+
+        try
+        {
+            UserDetails ud = null;
+            if (userName.equals(SYSTEM_USER_NAME))
+            {
+                GrantedAuthority[] gas = new GrantedAuthority[1];
+                gas[0] = new GrantedAuthorityImpl("ROLE_SYSTEM");
+                ud = new User(SYSTEM_USER_NAME, "", true, true, true, true, gas);
+            }
+            else if (userName.equalsIgnoreCase(PermissionService.GUEST_AUTHORITY))
+            {
+                GrantedAuthority[] gas = new GrantedAuthority[0];
+                ud = new User(PermissionService.GUEST_AUTHORITY.toLowerCase(), "", true, true, true, true, gas);
+            }
+            else
+            {
+                if (providedDetails.getUsername().equals(userName))
+                {
+                    ud = providedDetails;
+                }
+                else
+                {
+                    throw new AuthenticationException("Provided user details do not match the user name");
+                }
+            }
+
+            UsernamePasswordAuthenticationToken auth = new UsernamePasswordAuthenticationToken(ud, "", ud
+                    .getAuthorities());
+            auth.setDetails(ud);
+            auth.setAuthenticated(true);
+            return setCurrentAuthentication(auth);
+        }
+        catch (net.sf.acegisecurity.AuthenticationException ae)
+        {
+            throw new AuthenticationException(ae.getMessage(), ae);
+        }
+    }
+
+    /**
+     * Default implementation that makes an ACEGI object on the fly
+     * 
+     * @param userName
+     * @return
+     */
+    private static UserDetails getDefaultUserDetails(String userName)
+    {
+        GrantedAuthority[] gas = new GrantedAuthority[1];
+        gas[0] = new GrantedAuthorityImpl("ROLE_AUTHENTICATED");
+        UserDetails ud = new User(userName, "", true, true, true, true, gas);
+        return ud;
+    }
+
+    /**
+     * Explicitly set the current authentication.
+     * 
+     * @param authentication
+     *            Authentication
+     */
+    public static Authentication setCurrentAuthentication(Authentication authentication)
+    {
+        Context context = ContextHolder.getContext();
+        SecureContext sc = null;
+        if ((context == null) || !(context instanceof SecureContext))
+        {
+            sc = new SecureContextImpl();
+            ContextHolder.setContext(sc);
+        }
+        else
+        {
+            sc = (SecureContext) context;
+        }
+        authentication.setAuthenticated(true);
+        sc.setAuthentication(authentication);
+        return authentication;
+    }
+
+    /**
+     * Get the current authentication context
+     * 
+     * @return Authentication
+     * @throws AuthenticationException
+     */
+    public static Authentication getCurrentAuthentication() throws AuthenticationException
+    {
+        Context context = ContextHolder.getContext();
+        if ((context == null) || !(context instanceof SecureContext))
+        {
+            return null;
+        }
+        return ((SecureContext) context).getAuthentication();
+    }
+
+    /**
+     * Get the current user name.
+     * 
+     * @return String
+     * @throws AuthenticationException
+     */
+    public static String getCurrentUserName() throws AuthenticationException
+    {
+        Context context = ContextHolder.getContext();
+        if ((context == null) || !(context instanceof SecureContext))
+        {
+            return null;
+        }
+        return getUserName(((SecureContext) context).getAuthentication());
+    }
+
+    /**
+     * Get the current user name
+     * 
+     * @param authentication
+     *            Authentication
+     * @return String
+     */
+    private static String getUserName(Authentication authentication)
+    {
+        String username = authentication.getPrincipal().toString();
+
+        if (authentication.getPrincipal() instanceof UserDetails)
+        {
+            username = ((UserDetails) authentication.getPrincipal()).getUsername();
+        }
+
+        return username;
+    }
+
+    /**
+     * Set the system user as the current user.
+     * 
+     * @return Authentication
+     */
+    public static Authentication setSystemUserAsCurrentUser()
+    {
+        return setCurrentUser(SYSTEM_USER_NAME);
+    }
+
+    /**
+     * Get the name of the system user
+     * 
+     * @return String
+     */
+    public static String getSystemUserName()
+    {
+        return SYSTEM_USER_NAME;
+    }
+
+    /**
+     * Get the name of the Guest User
+     */
+    public static String getGuestUserName()
+    {
+        return PermissionService.GUEST_AUTHORITY.toLowerCase();
+    }
+
+    /**
+     * Remove the current security information
+     */
+    public static void clearCurrentSecurityContext()
+    {
+        ContextHolder.setContext(null);
+    }
+
+    public static <R> R runAs(RunAsWork<R> runAsWork, String uid)
+    {
+        String currentUser = AuthenticationUtil.getCurrentUserName();
+
+        R result = null;
+        try
+        {
+            AuthenticationUtil.setCurrentUser(uid);
+            result = runAsWork.doWork();
+            return result;
+        }
+        catch (Throwable exception)
+        {
+
+            // Re-throw the exception
+            if (exception instanceof RuntimeException)
+            {
+                throw (RuntimeException) exception;
+            }
+            else
+            {
+                throw new RuntimeException("Error during run as.", exception);
+            }
+        }
+        finally
+        {
+            AuthenticationUtil.clearCurrentSecurityContext();
+            if (currentUser != null)
+            {
+                AuthenticationUtil.setCurrentUser(currentUser);
+            }
+        }
+    }
+}