Could be a leak around one of the rear windows or possibly around the tail light.

Pop out the rear passenger side speaker grill and have a look inside. Might find where the leak is this way.

Logansportage <img src="/forums/images/graemlins/patriot.gif" alt="" />

White 1998 4 door KIA Sportage 4x4 w/Eibach 2.5 spring lift and TJ rear coils, 4crawler 1.5 body lift, Monroe Sensa.trac shocks, Bosch 4+ plugs, Eaton LSD, 31x10.5x15 BFG KM tires, 2.5 cat back exhaust w/SpinTech muffler