Visual C++ .net Rebuilds Libs Each IDE Startup

I'm using Visual C++ 7.2 to build Torque. I've set up my Solution so that the projects which generate the .lib and .dll files that Torque needs to build are dependencies of the Torque project. This seems to work out well for the most part, except for right after when I restart the IDE -- then it seems to have forgotten that it's ever built any of the libs, and when I tell it to build Torque, it rebuilds them all from scratch. (It doesn't recompile the C++ files in Torque itself, after that; it just relinks.)

Do any of you have any ideas of why this might be going on, and what I can do to stop it, short of removing those dependencies which I've set up?

Thanks in advance for your help!