Is it possible to set preprocessor macro in sln file and not in a project? (VS2008 c++)

I am maintaining a large codebase and some vcproj files are used in different solutions. Due to some horrendous configuration and dependencies it seems the best way to handle some build issues is to #ifdef the code but in order to do that I need to set a preprocessor definition at the solution file level and not at the vcproj level.

Is that possible?

How to do it?