Well, it sounds good on paper, but the fact is that there are hard coded limitations due to ISA being a 32bit application written to run on a 32bit platform.
For the details, check out this great article by Jonathan Barner on why the /3GB switch, PAE and AWE (Address Windowing Extensions) aren’t much help at pushing ISA past it’s 32bit heritage.
The good news is that the TMG firewall is a native 64bit application and thus isn’t exposed to these limitations.
Thomas W Shinder, M.D., MCSE
Sr. Consultant / Technical Writer