diff --git a/include/functions.php b/include/functions.php
index a9786e49b..107a02843 100644
--- a/include/functions.php
+++ b/include/functions.php
@@ -728,7 +728,7 @@
 	// this is used for user http parameters unless HTML code is actually needed
 	function clean($param) {
 		if (is_array($param)) {
-			return array_map(strip_tags, $param);
+			return array_map("strip_tags", $param);
 		} else if (is_string($param)) {
 			return strip_tags($param);
 		} else {