Joel has added two new ucsh functions which UCs can use to help people remove lock files that would stop firefox or mozilla from running. They are: remove_firefox_lock and remove_mozilla_lock. To see how to run them run them with no options.
Versions of these scripts are available for the user to run on their own. They take no options and are named user_remove_firefox_lock and user_remove_mozilla_lock. They currently reside in /u/uc/bin/ but should be moving to /usr/local/bin/.