diff --git a/phpgwapi/inc/class.common.inc.php b/phpgwapi/inc/class.common.inc.php
index 862c7648b9..974c0908cb 100644
--- a/phpgwapi/inc/class.common.inc.php
+++ b/phpgwapi/inc/class.common.inc.php
@@ -1411,7 +1411,7 @@
 					$format .= 'H:i';
 				}
 			}
-                        if((PHP_OS == 'Windows'||PHP_OS == 'WINNT') && (int)$t < 21600)
+			if((PHP_OS == 'Windows' || PHP_OS == 'WINNT') && (int)$t < 21600)
 			/*if(PHP_OS == 'Windows' && (int)$t < 21600)*/
 			{
 				$t = 21600;
diff --git a/phpgwapi/inc/class.sessions.inc.php b/phpgwapi/inc/class.sessions.inc.php
index 4ff38489d3..7c0f7d50e9 100644
--- a/phpgwapi/inc/class.sessions.inc.php
+++ b/phpgwapi/inc/class.sessions.inc.php
@@ -353,7 +353,9 @@
 
 			if (@$GLOBALS['phpgw_info']['server']['sessions_checkip'])
 			{
-				if (PHP_OS != 'Windows' && (! $GLOBALS['phpgw_info']['user']['session_ip'] || $GLOBALS['phpgw_info']['user']['session_ip'] != $this->getuser_ip()))
+				if((PHP_OS != 'Windows') && (PHP_OS != 'WINNT') &&
+					(!$GLOBALS['phpgw_info']['user']['session_ip'] || $GLOBALS['phpgw_info']['user']['session_ip'] != $this->getuser_ip())
+				)
 				{
 					if(is_object($GLOBALS['phpgw']->log))
 					{
@@ -752,9 +754,11 @@
 				return False;
 			}
 
-			if (@$GLOBALS['phpgw_info']['server']['sessions_checkip'])
+			if(@$GLOBALS['phpgw_info']['server']['sessions_checkip'])
 			{
-				if (PHP_OS != 'Windows' && (! $GLOBALS['phpgw_info']['user']['session_ip'] || $GLOBALS['phpgw_info']['user']['session_ip'] != $this->getuser_ip()))
+				if((PHP_OS != 'Windows') && (PHP_OS != 'WINNT') &&
+					(!$GLOBALS['phpgw_info']['user']['session_ip'] || $GLOBALS['phpgw_info']['user']['session_ip'] != $this->getuser_ip())
+				)
 				{
 					if(is_object($GLOBALS['phpgw']->log))
 					{
diff --git a/phpgwapi/inc/common_functions.inc.php b/phpgwapi/inc/common_functions.inc.php
index 75f328e4d1..128d6c70af 100755
--- a/phpgwapi/inc/common_functions.inc.php
+++ b/phpgwapi/inc/common_functions.inc.php
@@ -935,7 +935,7 @@
 	*/
 	function filesystem_separator()
 	{
-		if (PHP_OS == 'Windows' || PHP_OS == 'OS/2')
+		if(PHP_OS == 'Windows' || PHP_OS == 'OS/2' || PHP_OS == 'WINNT')
 		{
 			return '\\';
 		}