If your alternator and battery check out and the jump worked, it sounds like the battery got drained by something, either a device or bad ground. Keep an eye on it for a few days and see if it happens again. If you continue to have a problem, look for any add-on circuits, like for running lights or any additional equipment. The culprit is usually something like that rather than an OEM circuit.

I had the battery drained once when I took the VX in to a full service car wash. When they were wiping out the interior, they left the map lights on in the mirror. Sat all day with them on, then over night (I hadn't left the house or I would have noticed it). The overnight drain was enough to discharge the battery to the point where it wouldn't start.

If all else fails, you can have an auto electrician put a meter on your battery when you car is shut down, see what type of current draw may still be there (should be some load there if your alarm is on). I'm not sure what it's supposed to read, but I seem to remember another thread where it's discussed? Anyone?

-- John