When I check out code that contains two files with names that differ only in case, subversion gags with some odd message about the file not exisitng. The checkout works fine on Linux.
The problem is that the default Mac OS/X HFS file system is case-insensitive-but-case-preserving. Check out on linux, rename (svn mv) the files and the checkout will work on the Mac. Or install a case-sensitive HFS on your Mac.