problems with lipo on macos

Hi!

since the first time I compiled llvm for 32 and 64 on macos
(xcode 3.2) I get errors from lipo which I so far ignored since they
only occur for the executables but I only need the libraries. but
It would be interesting if someone knows where they come
from. They look like this:

CreateUniversalBinary build/llvm/bin/Debug/opt normal "i386 x86_64"
cd /Users/jwilhelmy/Coding/Lib/llvm
/usr/bin/lipo -create /Users/jwilhelmy/Coding/Lib/llvm/build/llvm/tools/opt/LLVM.build/Debug/opt.build/Objects-normal/i386/opt /Users/jwilhelmy/Coding/Lib/llvm/build/llvm/tools/opt/LLVM.build/Debug/opt.build/Objects-normal/x86_64/opt -output /Users/jwilhelmy/Coding/Lib/llvm/build/llvm/bin/Debug/opt

/usr/bin/lipo: can't open input file: /Users/jwilhelmy/Coding/Lib/llvm/build/llvm/tools/opt/LLVM.build/Debug/opt.build/Objects-normal/i386/opt (No such file or directory)
Command /usr/bin/lipo failed with exit code 1

-Jochen