'98 ML320 stalls when cold

[Chevota]

It starts ok, but stalls when put into gear when cold. The longer you let the engine warm up, the less of a problem it is. Sounds like a classic fuel enrichment issue to me, any suggestions on the cause?
It has 75K on it, the MAF has ~30K on it, new battery, no engine light, everything else seems ok. It's my mothers car now, so this isn't first hand info, but it was mine up until a few weeks ago and it worked fine then.
She says it's about 50 degrees in the AM when she's having the problem.

Thanks.....