> On the off-chance that you have any spare time to devote to R&D, do you think you could take a stab at using your menulistener class to intercept the HWND of a menu created through DEFINE POPUP?

This menu seems to be VFP own creation, not a Windows menu or popup. The menu listener cannot be apply to it in no way.

I spent some time yesterday running Spy++ and watching how this guy behaves.

As you saw probably, the window's class is "vfp994000003" and it has WM_POPUP style. Probably it's possible to find it through window enumeration.