Squid and F-Secure updates

[jarlel]

How can I setup squid so that it caches virus-definition updates for the F-Secure antivirus package?

All of the requests look like this (where the last part with the numbers differs a bit):

http://fsbwserver.f-secure.com/8/FR/167f8ae0/infopak.zip/2097152_2097152_3b697ceb1cf7747d

Not sure how to create the regexp that matches on this one. Does anybody know?

Thanks.