Email validation not working in Internet Explorer

Script with email address validation doesn't work in Internet Explorer

[gcan]

Hello,

Can somebody help me? I don't understand why my script stops working in Internet Explorer if I include the following lines:
=================================

var email = $("input#email").val(); 
var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/; 
if (!filter(email)) { 
$("label#email_error").show(); 
$("input#email").focus(); 
return false;

================================

It works fine with all other browsers.
Thanks.

[whoisgregg]

A couple things jump out at me. First, there's a missing closing curly brace "}" (but perhaps it exists in the rest of the code). Second, the regular expression isn't wrapped in any kind of quotes. Directly in a call to a function that accepts a regex pattern you skip the quotes, but it might be confusing IE the quotes don't exist when you're storing the regex in a variable?