I had the same problem on my 2000 a few months ago. As mentioned above, it was the catch on the latch being stuck in the closed position. Doing this from memory, so hopefully it'll be even remotely accurate...
Remove the interior hatch panel. If you look at the latch assembly, you should be able to see the catch pushed forward. Use a couple of screwdrivers to push it back into place; from what I remember, there's a small locking armature that needs to be prised forwards to free the catch. This should be found back inside the latch assembly where the catch curves inwards towards its pivot point. It's a little fiddly to get at, but should only take a couple of minutes to free up.
Sorry for the flaky description - I've only had to do this once, and like I said it was some time ago. Hopefully it'll make more sense when you look at it.