MozPlugger (Plugin to launch external viewers in Mozilla)

It allows you to integrate external applications to view files
that Mozilla can't handle itself.

MozPlugger was branched out from Plugger 4.0 in 
February 2003 by Louis Bavoili.

Homepage: http://mozplugger.mozdev.org/

You may need to delete your local $HOME/.mozilla/firefox/pluginreg.dat 
file for mozplugger to be enabled correctly after you update it.