[squid-users] proxy.pac-Bug in IE?

Hi there,

I have the following proxy.pac file:

===
function FindProxyForURL(url, host)
{
if (isPlainHostName(host) ||
dnsDomainIs(host, ".effenberger"))
return "DIRECT";
else
return "PROXY nibbler.effenberger:3128";
}
===

What I want to achieve is that

1.) plain hostnames are accessed directly
2.) hostnames ending in .effenberger (my local domain) are
accessed directly
3.) all other connections should be accessed via my proxy

It works fine in Mozilla, Opera and Konqueror, but not in Internet Explorer.
If I open up any domain with ".effenberger.", it does not work. Example:
www.effenberger.de, www.effenberger.com, etc.

Is this a bug in IE?

Thanks for your help!
Florian