Calling all technical gurus! (non-autox content follows)

["Brad Cox" <coxb@trimofran.org>]

I am posting a question for a list impaired friend.  He has a leak in
the plastic tank on his Porsche 928.  it's very small, and in a very
accessible location.  He has tried some sort of patching material made
by "Goop", but I don't know if it was specific for his application.
The patch held for awhile, but gave way when the tank became
pressurized.  Does anyone have experience patching plastic gas tanks?
And if so, what did you patch them with?  Thanks!!!

-Brad