Has anyone worked out how to use AHAH within a custom multi-field cck field? I noticed someone had an issue posted some time ago that did not result in a solution.

The issues I'm running into when trying to populate a select based on the selection from another select are:
1) Identifying the selected value from the 'parent' (AHAH-enabled) select list
2) Identifying the correct delta to use
3) Locating the correct path to place the AHAH response.

Can this presently be done? Or shall I look into patching CCK itself? Ideas?