I found a couple threads in the Sprint section on camera freeze problem.

I just encountered it today on the AT&T Pre+.

I had the camera open, then my phone went to screen lock. I unlocked it and the camera was stuck on the "grey screen of death." I closed the camera app and opened it again, but it was still stuck on the grey screen. I swiped back, closed, opened..nothing was working. Finally after about 1 minute, it just opened back up correctly on its own.

I saw on some Palm forums that there was a supposed firmware update to fix it, but AT&T is running 1.4.2 (newer than Sprint) so looks like it's not cured yet.

Anyone else experience a camera freeze up?