ANTI-SURBL technique used by spammer

[Nick Gilbert]

I think this is well known already(?), but I've just noticed a spammer 
doing something rather annoying:

<a 
href=http://www.imageusa.com/bannerclick.asp?url=http://www.google.com>www.google.com</a>

This links to Google via an innocent site which has nothing to do with 
the spammer. (note, obviously Google was not the linked site used by the 
spammer - I've changed it to ensure this gets though everyone's spam 
filters).

Does the SURBL client check parameters of the referenced pages as well 
as the actual base url?

Nick...