It is strange that this only started happening recently. As far as I know, a lot of people were using the latest large statusbar clock for weeks before this started to happen. Personal Menu doesn't seem to be installed for everyone it is happening to.

It seems like a recently updated package has done something. I updated modest, started having the problem, removed modest and have not had a single reset since Saturday while running the clock and personal menu. I know some people have never even installed modest and are having the problem, so I am flummoxed.