Thanks, that helped, I added this line in  tools/build/v2/tools/darwin.jam:
   iphone-3.0 iphonesim-3.0

I'm now having an error message saying: error: unrecognized command line option: "-Wno-long-double"
I solved that by taking this out:

    # - GCC 4.2 and higher in Darwin does not have -Wno-long-double.
    if $(version) < "4.2.0"
    {
        flags darwin.compile OPTIONS $(condition) : -Wno-long-double ;
    }

What's the clean here, does anybody know?

Thanks,
Frank