diff --git a/lib/plugins/plugin.inc.php b/lib/plugins/plugin.inc.php
index 2e8871f..853fb8f 100644
--- a/lib/plugins/plugin.inc.php
+++ b/lib/plugins/plugin.inc.php
@@ -356,12 +356,14 @@ class KTPlugin {
         if (empty($sFilename)) {
             $sFilename = $this->sFilename;
         }
+
         if (!KTUtil::isAbsolutePath($sFilename)) {
             if ($this->sFilename) {
                 $sDirPath = dirname($this->sFilename);
                 $sFilename = sprintf("%s/%s", $sDirPath, $sFilename);
             }
         }
+        $sFilename = str_replace('\\', '/', $sFilename);
         return $sFilename;
     }
 
diff --git a/lib/util/ktutil.inc b/lib/util/ktutil.inc
index bb8f3b0..d69ef1a 100644
--- a/lib/util/ktutil.inc
+++ b/lib/util/ktutil.inc
@@ -749,6 +749,11 @@ class KTUtil {
     // {{{ isAbsolutePath
     static function isAbsolutePath($sPath) {
 
+        $sPath = str_replace('\\', '/', $sPath);
+        $sReal = str_replace('\\', '/', realpath($sPath));
+
+        return ($sReal == $sPath);
+
         if (substr($sPath, 0, 1) == '/') {
             return true;
         }
diff --git a/plugins/ktcore/KTDocumentActions.php b/plugins/ktcore/KTDocumentActions.php
index a95a71b..1f19c5c 100644
--- a/plugins/ktcore/KTDocumentActions.php
+++ b/plugins/ktcore/KTDocumentActions.php
@@ -171,15 +171,17 @@ class KTDocumentVersionHistoryAction extends KTDocumentAction {
 
         if($isActive){
             $oRegistry =& KTPluginRegistry::getSingleton();
-    		$oPlugin =& $oRegistry->getPlugin('document.comparison.plugin');
-    		$oPlugin->load();
-    		$sUrl = $oPlugin->getPagePath('DocumentComparison');
-    		$file = $oPlugin->_aPages['document.comparison.plugin/DocumentComparison'][2];
+            $oPlugin =& $oRegistry->getPlugin('document.comparison.plugin');
+            
+            if($oPlugin->load()){
+                $sUrl = $oPlugin->getPagePath('DocumentComparison');
+                $file = $oPlugin->_aPages['document.comparison.plugin/DocumentComparison'][2];
 
-    		include_once($file);
+                include_once($file);
 
-            // Check mime type of document for content comparison
-            list($bShowCompare, $bShowVersionCompare) = DocumentComparison::checkMimeType($this->oDocument);
+                // Check mime type of document for content comparison
+                list($bShowCompare, $bShowVersionCompare) = DocumentComparison::checkMimeType($this->oDocument);
+            }
         }
 
         $aTemplateData = array(