Tim,

The jam nut that holds the cable in position for the rear latch (yes, there
are two latches on the door) has probably come loose.  My '83 does it all
the time.  To fix, remove the upolstery from the inside of the door and
tighten up the nut on the cable housing.  Then it will open.

Good luck.  It IS an easy fix...

Jim

>Yup, the sliding door on my '84 vanagon is stuck.  I tried to open it from
>the outside, and the handle felt and sounded like I disengaged the door
>mechanism (ya know what I mean, the sound and feel it makes when you open
>the door).  However, the door didn't open at all.  Simillarly, the inside
>handle has no tension on it, as if the door opening mechanism was stuck.