Linker warnings with Xcode 3.2.2

I just upgraded Xcode to 3.2.2. Now I am getting a lot of linker warnings along the lines "Directory '/path/to/a/search/path' following -F not found."

The search path in question does indeed not exist for me, but on the other hand it /may/ exist (and be needed) depending on the Xcode preference setting. And the project in question is shared between developers with (possibly) different settings.

Does anyone know how to turn off these warnings, perhaps a setting of WARNING_LDFLAGS?

Thanks,
Christiaan