Due to recent requests, I changed the compiler's symbol writer to write the debugging information into a separate symbol file. These files are called Foo.exe.mdb and Foo.dll.mdb and are installed in the same directory than the assembly. This step will allow us to package the symbol files in a separate debugging package and thus make the size of Mono's main packages smaller.
I did not have much time to look at the whole build stuff, so things may be a bit messed up at the moment. If you discover any problems, please let me know.