diff --git a/email/Email.php b/email/Email.php
index c1d08a46d..a5c37fe24 100644
--- a/email/Email.php
+++ b/email/Email.php
@@ -560,7 +560,7 @@ class Email extends ViewableData {
 	 * 	This code is licensed under a Creative Commons Attribution-ShareAlike 2.5 License 
 	 * 	http://creativecommons.org/licenses/by-sa/2.5/
 	 */
-	function is_valid_address($email){
+	public static function is_valid_address($email){
 		$qtext = '[^\\x0d\\x22\\x5c\\x80-\\xff]';
 		$dtext = '[^\\x0d\\x5b-\\x5d\\x80-\\xff]';
 		$atom = '[^\\x00-\\x20\\x22\\x28\\x29\\x2c\\x2e\\x3a-\\x3c'.