Index: t3lib/class.t3lib_div.php
===================================================================
--- t3lib/class.t3lib_div.php	(revision 8578)
+++ t3lib/class.t3lib_div.php	(working copy)
@@ -1291,12 +1291,18 @@
 	 * @param	string		Reference string which must be found as the "first part" of the full string
 	 * @return	boolean		True if $partStr was found to be equal to the first part of $str
 	 */
-	public static function isFirstPartOfStr($str,$partStr)	{
+	public static function isFirstPartOfStr($str, $partStr) {
+			// ensure variables are strings
+		$str = (string) $str;
+		$partStr = (string) $partStr;
+
 		// Returns true, if the first part of a $str equals $partStr and $partStr is not ''
-		$psLen = strlen($partStr);
-		if ($psLen)	{
-			return substr($str,0,$psLen)==(string)$partStr;
-		} else return false;
+		$partLength = strlen($partStr);
+		if ($partLength) {
+			return substr($str, 0, $partLength) === $partStr;
+		} else {
+			return FALSE;
+		}
 	}
 
 	/**