diff --git a/lib/filecache.php b/lib/filecache.php
index 811e8a3e6a..de38ad99e8 100644
--- a/lib/filecache.php
+++ b/lib/filecache.php
@@ -474,6 +474,20 @@ class OC_FileCache{
 		$query=OC_DB::prepare('DELETE FROM `*PREFIX*fscache` WHERE LENGTH(`path_hash`)<30');
 		$query->execute();
 	}
+
+	/**
+	 * clear filecache entries
+	 * @param string user (optonal)
+	 */
+	public static function clear($user=''){
+		if($user){
+			$query=OC_DB::prepare('DELETE FROM `*PREFIX*fscache` WHERE user=?');
+			$query->execute(array($user));
+		}else{
+			$query=OC_DB::prepare('DELETE FROM `*PREFIX*fscache`');
+			$query->execute();
+		}
+	}
 }
 
 //watch for changes and try to keep the cache up to date
diff --git a/lib/filesystem.php b/lib/filesystem.php
index c69970467f..01467b54c8 100644
--- a/lib/filesystem.php
+++ b/lib/filesystem.php
@@ -236,6 +236,13 @@ class OC_Filesystem{
 					}
 				}
 			}
+
+			$mtime=filemtime(OC::$SERVERROOT.'/config/mount.php');
+			$previousMTime=OC_Appconfig::getValue('files','mountconfigmtime',0);
+			if($mtime>$previousMTime){//mount config has changed, filecache needs to be updated
+				OC_FileCache::clear();
+				OC_Appconfig::setValue('files','mountconfigmtime',$mtime);
+			}
 		}
 
 		self::$loaded=true;