It's a Winzip thing. I'll bet wampum generator is a .tar file, just rename it to a .tgz file and it should open just fine.
Just some thoughts/guesses: I'll bet Kathy uses Internet Explorer. Don't know about Netscape, but it becomes more and more difficult to get IE _not_ to try to be "smart" about any file you download. In this case I think there's some kind of transparent mechanism which kicks in and tries to transparently decompress files of type application/x-tar. Guess it's a helper for compressed vrml .wrl.gz (or similar) files. In this case renaming to .tgz works, but I think I saw the same mess the other way around when IE didn't remove the .gz suffix but nonetheless transparently decompressed the file. These things are extremely annoying when dealing with relativly unexperienced clients who, say, just want to _download_ an .avi file with a left-klick. MS has implemented a lot of magic there, AFAIK IE even tries to guess the filetype by its content in some cases and then ignores each and every http-header which might suggest otherwise. Adding "Content-Disposition: attachment" as a http-header seems to help (for the .avi case). cheers, oliver