Stalling problems?

[TM]

Listers,
Have you experienced this symptom:

Driving along, engine warm, coasting as I slow,
I put the clutch in. Revs drop to 0 as the car stalls.
No problem starting the car back up, then runs fine.

Is the car hypersensitive in 3rd and 4th gear for
some reason, if I try to let it coast in gear? I never
had this problem in the 5ktq. It is an intermittent
problem (of course), affecting me only three times so
far. I'm wondering why the engine would stumble and stall
like this (if it is a stumble, no real sound indication
as such).

Could this be a case of the clutch not disengaging immediately
when I depress the pedal? Would that be a possible impending
clutch master/slave cylinder failure?

I'm stumped.

Taka
'91 200q