[squid-users] Squid dstdomain ACL

All,

I have a fairly busy cache using native squid ACLs to block access to
certain sites using the dstdomain ACL type. This is fine for denying =
access
to sites like www.playboy.com, but doesn't work when people use google's
cache of pages and google images, since the domain becomes =
www.google.com.

My question; is there an ACL that will deny both
http://www.playboy.com and
http://www.google.com/search?q=3Dcac....playboy.com/?

I know regexes might be able to do this, but will there be a performance
hit?

Thanks.

Mike