Where is object.d? Will it work on 10.6?

[al]

I've installed GDC on 10.6 using provided installer. However, when I try to compile anything, it stops with error:

object.d: module object cannot read file 'object.d'

So far I know it's because it can't find includes, but I don't know where it expects them. 

gdc -print-search-dirs gives me library dirs, not source include dirs.

Can it be caused by conflict with DMD? I've got leftovers from DMD1 and DMD2 on my system (they were too buggy to work with :/)

i686-apple-darwin9-gdc-4.0.1 (GCC) 4.0.1 (Apple Inc. build 5484)