Automatically add new wireless access points

I'm running Lucid on a few laptops, with xfce as the desktop environment.

Before Lucid, the little NetworkManager tray widget would automatically scan for access points for me. Now, however, I find that I have to go run iwlist myself to look for SSIDs (if I don't know one already) and manually add that to the list. Once I've done that, then it'll automatically connect (if the AP is configured that way).

Part of what makes this a real pain is that the tray widget (sometimes) seems to not show itself at all when there's no current connection and no known access points. I have to kill NetworkManager (which is a pain, because init really wants to re-launch it), run iwlist to find an SSID, go to the (now showing) tray widget and add the SSID, and then re-start NetworkManager.

I realize that the widget is just messing with a config file or two, and I'm happy to fool with those manually, but what I'd really like is for it to work the way it used to and just do the scan for me. Note that once I've got a connection up, then it shows me all the APs it can see, as before.

I acknowledge that it's possible I screwed up some setup file, but I've really tried scrubbing everything back to "as new" state and that hasn't helped. Am I crazy or did that stuff really change?