skip900

This is my first post so I hope I do this right. I have a 2002 and the last year or two I have noticed rust at window joint at bottom of liftgate. It seems that water is forced down to this area by the rear wiper and the fact that there is no spoiler to divert water running off roof. Does anyone have this same problem? The rust seems a bit premature. Dealer says its not covered. Any suggestions? Thanks a lot. Skip