I think this problem came up on some early '00 TJ's too. (I uh, worked there then...) Normally, the cam sensor (goes where the distributor used to be) seizes, and strips the gears off it's drive, which stops the oil pump. The oil pressure drops to zero and the "check guages" light and chime goes off. If you shut it off, it won't restart, but so long as you don't shut it off, it'll run fine. (w/o oil pressure!) Just curious, but do you have any idea how long you drove with zero oil pressure? Not that it's your fault, just wondering how fast things go south. My old chev straight six would starve for oil quite a bit at times, (it leaked a LOT) and the bearings all looked fine when I ripped it apart for fun.
As for a fix, I don't know of a good one... We just swapped a new sensor in, changed the oil, and sent them back out. WATCH YOUR OIL PRESSURE GUAGE! If it suddenly drops to zero and the chime and light go bingo, pull over and shut it off ASAP! If it won't restart, you just saved your engine, and the sensor is only like $50 or so I think. Roll it to #1 TDC, drop the new sensor in, pull the alignment pin, and off you go again! (The cam gears seem to be much stronger than the dist/sensor drive gears.)
Change the oil ASAP too, and it wouldn't hurt to fish around a little with a magnet, or get a mag drain plug after that too.
C