diff --git a/phpgwapi/inc/class.sessions_db.inc.php b/phpgwapi/inc/class.sessions_db.inc.php
index 09c2c4d52c..1f8982c810 100644
--- a/phpgwapi/inc/class.sessions_db.inc.php
+++ b/phpgwapi/inc/class.sessions_db.inc.php
@@ -322,7 +322,7 @@
 				return False;
 			}
 
-			if (! $GLOBALS['phpgw']->auth->authenticate($this->account_lid, $this->passwd, $this->passwd_type))
+			if (! $GLOBALS['phpgw']->auth->authenticate($this->account_lid, $this->passwd, $this->passwd_type) || $GLOBALS['phpgw']->accounts->get_type($this->account_lid) == 'g')
 			{
 				return False;
 				exit;
diff --git a/phpgwapi/inc/class.sessions_php4.inc.php b/phpgwapi/inc/class.sessions_php4.inc.php
index 4f8a2eff55..0ddebb562f 100644
--- a/phpgwapi/inc/class.sessions_php4.inc.php
+++ b/phpgwapi/inc/class.sessions_php4.inc.php
@@ -306,7 +306,7 @@
 				return False;
 			}
 
-			if (! $GLOBALS['phpgw']->auth->authenticate($this->account_lid, $this->passwd, $this->passwd_type))
+			if (! $GLOBALS['phpgw']->auth->authenticate($this->account_lid, $this->passwd, $this->passwd_type) || $GLOBALS['phpgw']->accounts->get_type($this->account_lid) == 'g')
 			{
 				return False;
 				exit;