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Solution: When running this test perl is evidently in "taint" mode which means that it's checking to see that no one could do anything nasty on your computer during the install. In this particular case, it is checking all the directories in your path to see that no one other than the owner can write into that directory. If one of those directories was world-writeable then an evil person could put an executable in there that could then be run by you, which would be a Bad Thing. Thus, make sure all of the directories in your path ("echo $path") are not world writeable. (This fixed an install problem for me on OS X 10.3.5, but I imagine it's applicable to other OSs as well.)