Have you ever wondered why Forefront TMG Client shows up on Task Manager as a 32bit process? Many Firewall Admins start wondering why this happens even when they know that TMG 2010 is a full 64bit application. The simple is "this is an expected behavior."
"TMG client package supports both 32 and 64-bit Windows and on 64-bit Windows supports both 32- and 64-bit processes. The FwcMgmt and FwcAgent processes don't use any of the capabilities that're only available for 64-bit processes (e.g. larger memory space) so it was decided that having both 32-bit and 64-bit flavors isn't worth the effort. However, it's important to notice that the WinSock Layered Service Provider component of TMG client is actually 64-bit as shown below":
"Since WinSock LSP are loaded inproc by WinSock app, the provider must have same "bit-ness" as the client app. Hence two DLLs, FwcWsp.dll and FwcWsp64.dll, supporting 32 and 64-bit apps, respectively. The "bit-ness" of FWC processes (management tools) doesn't have to match the "bit-ness" of any app and hence having them 32-bit is good enough," explained Microsoft.