It looks like up to '02 for the 32RH/999 and up to '06 for the 42RLE which should be the same torque converter. If I recall correctly, the 42 series is the 998/999 case modified slightly with extra oil passages and a new valve body for the overdrive in the tailshaft; so it should essentially be the same in all other places.
Edit: The RE and RLE are totally different transmissions. The 42RE is a 998/999 case, but the 42RLE is a 604 case.
The 42RE was available behind the 4.0 Grand Cherokee (WJ) from '99-'04.