Check your levels and consider putting some Lucas Transmission Fix in it. Also, I just had my TPS go out in my '04 WJ.. it was causing it to do all sorts of weird things like that. She'd start in high RPM sometimes, sometimes I'd be cruising on a flat highway and she'd just shift up for whatever reason.. run at a high RPM for a bit then shift back down. She'd also jump during idling and occasionally drop low enough to stall out. If you're interested in reading up on my post here it is:
('04 Jeep WJ | Engine/Trany Issues
Are you getting any form of error from the computer? If your check engine light as been coming on turn the key to the on position then off 3 times and it will show you the error code in the odometer. My codes where P0122 and P0123, both corresponding to Throttle/Pedal position. If you're not getting any form of error code from the computer I would lean a little more toward your trans.. a little Lucas could do it good.