[V6-12v] Leak from sunroof

[The CyberPoet]

I've come across a leak from our sunroof on the '93 Audi 100S (sedan) 
that is intermittent, depending on the angle the car is parked on. Best 
I can tell is that the drain from the rear passenger corner of the 
sunroof is compromised somewhere in it's route, since occasionally 
water pours out of the rear passenger side light fixture when the car 
first starts to move. Has anyone replaced their drain 
hoses/tubing/whatever in there, and if so, do you have any insight?

Cheers
=-= Marc Glasgow