Reverse Proxy through FW-1

[Myles_Keough () corpsoft com]

Has anyone tried to setup a Proxy server behind a FW-1?  I'm try to have users
log in with their NT accounts over the internet by doing the following; pass
through the firewall to the Proxy server (in DMZ), reverse proxy back through
the firewall to the intranet, then hit the IIS box.  The FW, Proxy, and IIS box
are all setup to do this but for some reason it's not working.  Any idea's?

Also, has anyone install a VPN-1 Accelerator Card?  How easy is it to install
and configure and more importantly is the performance increase noticeable?