This is REALLY un-intuitive. I spent hours trying to figure out how to create sub-menus in the Twenty Ten theme. I was using a custom menu already, so even if it works with default menu out of the box, it doesn’t work with custom menus.
Searching for how to get submenus working in Twenty Ten came up with many irrelevant results, and it took hours of wading through these to find this one post which helped, although incidentally.
gcc111…thanks for your post and the reference to the Gecka site. being a bit of a “noob”, I’ve been beating my brains for the last day or so trying to figure this out in a logical way. Watching the video answered my question completely.