My original post hasn't turned up yet, so this may be a duplicate. There was an earlier request (last year) by Massimo, with code written by Martin Mulone to address the dropdown button issue. It may have slipped through the system and never implemented.
https://groups.google.com/forum/#!searchin/web2py-developers/buttons$20in$20grid/web2py-developers/naPIG3ORfrY/f34knZoozfcJ --
