No Go!..tranny trouble

'97 sedan. Backed out of my space at work, put the car in forward, moved 1' and stopped. Shifter works, but no movement in either direction. Heard just the slightest clunk.

Car rolls, so tranny isn't frozen. If the finger shaft broke, then it should have left me in drive. The electric lock-out seems to be working properly.

Open to any and all suggestions.

...If I shift to PARK, it holds, so the parking cog is working. I can shift into any gear and the car rolls free.