Firefox Problem with External Links

Lately all external links (such as links in Instant messanger conversations and the "Online Documentation" link under System>Help) have opened to www.arizona.edu in firefox. I searched the web a bit and found this:

http://justlinux.com/forum/showthread.php?t=141984

In my System>Preferrences>Preferred Applications menu, my command for the web browser was "firefox32 %u". "Firefox32" is the command to start firefox 32-bit (which is what I use) and %u apparently returns the page with the highest google results for "u" which happens to be the University of Arizona... Very weird! I've never messed with these commands before. However, I tried changing the command back to simply "firefox32" but this just opens a blank tab when I click on an external link. What is the correct command I should have for the web browser in Preferred Applications?