This one's probably only for UNIX geeks who have customized their tcsh (or bash) environment with a .cshrc (or .bashrc or similar) file. I just got done debugging why the Canon ip3000 printer driver installer was hanging in the middle of installation.
It turns out that I had aliased rm to rm -i, so I would not clobber files as easily. Unfortunately, the Canon installer used my tcsh environment in its script. This is bad form, I would say.
Inside the script was a section that tried to delete some files using rm. Since the alias was present, it was waiting for me to say y but, of course, that was futile since it was not being run in a Terminal window. I removed the alias I had in my .cshrc, and the installer worked fine.
Mac OS X Hints
http://hints.macworld.com/article.php?story=2005071512423943