diff --git a/lib/validation.php b/lib/validation.php
index 6561ba3098c2404ba174b19d724fe31ad789ea2b..076ecb5ee301c6ee8811dae5cf97b45ce68bb2fc 100644
--- a/lib/validation.php
+++ b/lib/validation.php
@@ -160,7 +160,7 @@ function validSID($SID,$override){
 		}
 	}
 	else{
-		if(!eregi("^[0-9]*$", $SID) || strlen($SID) != 6){
+		if(!preg_match("/^[0-9]*$/", $SID) || strlen($SID) != 6){
 			$error = "Invalid student ID";
 			return false;
 		}