diff --git a/TODO b/TODO
index 6ec3360c..27848579 100644
--- a/TODO
+++ b/TODO
@@ -68,7 +68,7 @@ FIXED	 	 	0001210 		Add start- and endtime to autoresponder
  	 	 	0001211 		Generated MySQL username too long
  	 	 	0001208 		HTML Tags in Support Tickets
  	 	 	0001207 		FTP Passw�rter mit Umlauten
- 	 		0001201 		Virtualusers conflict with local users when using libnss-mysql
+FIXED	 	 	0001201 		Virtualusers conflict with local users when using libnss-mysql
  	 	 	0001204 		php5-suhosin
 FIXED	 	 	0001203 		Add check for PHP version and required PHP modules in install script
  	 	 	0001198 		More online help wanted
diff --git a/lib/functions/system/function.checklastguid.php b/lib/functions/system/function.checklastguid.php
new file mode 100644
index 00000000..02dc703b
--- /dev/null
+++ b/lib/functions/system/function.checklastguid.php
@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * This file is part of the Froxlor project.
+ * Copyright (c) 2010 the Froxlor Team (see authors).
+ *
+ * For the full copyright and license information, please view the COPYING
+ * file that was distributed with this source code. You can also view the
+ * COPYING file online at http://files.froxlor.org/misc/COPYING.txt
+ *
+ * @copyright  (c) the authors
+ * @author     Froxlor team <team@froxlor.org> (2010-)
+ * @license    GPLv2 http://files.froxlor.org/misc/COPYING.txt
+ * @package    Language
+ * @version    $Id: 185.spf.php 106 2010-01-25 10:06:34Z d00p $
+ */
+
+/*
+ * Function checkLastGuid
+ *
+ * Checks if the system's last guid
+ * is not higher than the one saved
+ * in froxlor's database.
+ * If it's higher, froxlor needs to
+ * set its last guid to this one
+ * to avoid conflicts with libnss-users
+ *
+ * @param	int		guid (from froxlor database)
+ *
+ * @return	null
+ */
+function checkLastGuid($froxlor_guid = 0)
+{
+	global $cronlog;
+
+	$group_lines = array();
+	$group_guids = array();
+	$update_to_guid = 0;
+
+	$g_file = '/etc/group';
+
+	if(file_exists($g_file))
+	{
+		if(is_readable($g_file))
+		{
+			if(true == ($groups = file_get_contents($g_file)))
+			{
+				$group_lines = explode("\n", $groups);
+
+				foreach($group_lines as $group)
+				{
+					$group_guids[] = explode(":", $group);
+				}
+
+				foreach($group_guids as $idx => $group)
+				{
+					$guid = $group[2];
+
+					if($guid > $froxlor_guid)
+					{
+						$update_to_guid = $guid;
+					}
+				}
+
+				if($update_to_guid > $froxlor_guid)
+				{
+					$cronlog->logAction(CRON_ACTION, LOG_NOTICE, 'Updating froxlor last guid to '.$update_to_guid);
+					saveSetting('system', 'lastguid', $update_to_guid);
+				}
+			}
+			else
+			{
+				$cronlog->logAction(CRON_ACTION, LOG_NOTICE, 'File /etc/group not readable; cannot check for latest guid');
+			}
+		}
+		else
+		{
+			$cronlog->logAction(CRON_ACTION, LOG_NOTICE, 'File /etc/group not readable; cannot check for latest guid');
+		}
+	}
+	else
+	{
+		$cronlog->logAction(CRON_ACTION, LOG_NOTICE, 'File /etc/group does not exist; cannot check for latest guid');
+	}
+}
diff --git a/scripts/cron_tasks.php b/scripts/cron_tasks.php
index 94ff36b8..eaba25f9 100644
--- a/scripts/cron_tasks.php
+++ b/scripts/cron_tasks.php
@@ -259,6 +259,14 @@ if($db->num_rows($result_tasks) != 0)
 
 $db->query('UPDATE `' . TABLE_PANEL_SETTINGS . '` SET `value` = UNIX_TIMESTAMP() WHERE `settinggroup` = \'system\'   AND `varname`      = \'last_tasks_run\' ');
 
+/*
+ * we have to check the system's last guid with every cron run
+ * in case the admin installed new software which added a new user
+ * so users in the database don't conflict with system users
+ */
+$cronlog->logAction(CRON_ACTION, LOG_NOTICE, 'Checking system\'s last guid');
+checkLastGuid($settings['system']['lastguid']);
+
 /**
  * STARTING CRONSCRIPT FOOTER
  */