Can it do it? Yes, but I don't recommend it. The "rating" is like 6500#'s I believe, but I don't care what the marketing department of Chrysler says, that is just too much weight for a ZJ to pull safely. Once you get a 4000# jeep, loaded up for the trail with spares and tools etc, add a trailer and some passengers in the tow rig and you're asking that little SUV to pull a lot of weight.
I used a v8 grand for about a year to pull my ~4000# buggy on a 1600# trailer. The vehicle had the power to do freeway speeds (60-70) on flat ground, but it didn't have the weight or stability to control the trailer if and when something bad happened. I towed to moab probably 3-4 times with it, and the last time I had to go down Price canyon in a snowstorm. Put it up for sale when I got home and purchased a 99 Dodge diesel. I didn't think I had the money, but I also decided my life wasn't worth the risk. There were a couple of times towing with my Dodge where I had to make an emergency turn or break to avoid something and I know for a fact that I wouldn't have wanted to be towing with that ZJ in those situations. I ended up taking a $2000 loss on the situation in a year since the tranny was slipping when I sold it which made it hard to sell for a reasonable price and I ended up upside down on it.
Also, it sucked in the summer months because there was no way you could run the A/C while towing. I got tired of being stressed about holding up traffic, about any side winds, adverse weather, and sweating my ass off coming across the desert in June with no AC and the engine running at 220# and 3000+ rpms (don't tow with the OD on in these things). What is a 3.5 hour leisurely drive in a normal vehicle or good tow rig was a 4.5 hour stressful drive towing in the ZJ.
The durango would be a better bet if you are set on a 1/4 ton SUV for a tow rig. The leaf springs, frame, and wheel base all suit it better to towing than the ZJ. I would personally move up to a 1/2 ton or 3/4 SUV options (expedition/excursion, suburban) or maybe a 4 door 1/2 v8 truck (dodge 1500, f150, chevy 1500, toy tundra etc).