yaCt: Car stalls when accelerating from a stop (sometimes)

[Mermaidman]

Wife has been complaining that her car sometimes stalls when she accelerates from a standstill. She then cranks the engine and drives away normally. What could be the problem? She's had the car for ~six months and this started about 3 months ago, but is becoming more frequent. Auto transmission, GM 4.0L V8 with ~45K miles. It has never happened when I'm driving or riding with her, so I can't give more detail.