Over the course of several Panther upgrades, I’ve noticed some files tend to not get updated. In one case, the java internet plugins did not get updated because their modification dates were set to the year 2010.
My suggestion is this: If you have DiskWarrior (you do, right?) run DiskWarrior on your disk first and repair any date and other disk issues.
Then do an archive and install (which is really a backup and install) of Panther. If you notice things not working properly, see your local consultant/dealer for a clean install of the OS.