Have you correctly set the clock on your machine? That problem usually comes up with there's a problem with timestamps. I'm guessing that if you do a "date", you'll find that it's wrong. If it's right, then "ls -l /usr/lib/perl/5.8/Config.pm" will give you a bad date.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?