The quickest way to do it will be to create a security group, make your user a member of that group then configure ISA to allow everything for that group, assuming of course the router is still using nat and is not DMZ'd through to the server (in other words, is still acting as a firewall.) I can't offer any more help as the last ISA server I used was on the 2000 platform and it's changed quite a bit for 2003.
