Sounds like taillight seals to me. When my trunk seal leaked, the WHOLE trunk was soaked. FYI, I have never heard of a rear window seal on a Jetta leaking. You may want to get in the trunk with a flashlight and have a friend spray water around the trunk seal, rear window, and taillights. You should be able to determine the source of the leak that way.
-Dave '91 Jetta GTX 16V (For Sale) '88 Jetta GLI 16V '81 Scirocco S (16V coming soon...)
