Some ajax nonfunctional on drupal commons

using CiviCRM 3.4.5 and the new acquia drupal commons 2.0

CiviCRM is working fine where I've used except that:

1) the dashboard elements can't be dragged or dropped on the home CiviCRM page (see image). The proper available dashlets appear as expected, and on admin pages the 'X' also appears, but the usual button-like decorations are absent, and they are inert. Passing the cursor over any of the dashlets changes the cursor properly, but nothing happens when clicked over an active spot.

2) essentially the same thing applies for the sort-order widgets at the top of sortable table columns. Again, the cursor responds actively, but clicking produces no effect and the up/down '^' images are absent.

Firebug reports no errors or exceptions. No css or js file fails to load.

3.4.5 works fine on other 6.22 drupal sites I've used.

I've tried applying different generic themes (non-commons, which are highly customized) to the CiviCRM segment of the site. The problem persists even though the alternative themes work OK in non-commons sites.

FWIW: Commons uses features/profiles and strongarm for distribution.