I tried this code here - http://wordpress.org/support/topic/plugin-tabbed-widgets-its-not-working?replies=5 - and the tabbed widget starts to show the 2 tabs multiplied.
I pressed F5 and the widget showed the list of just one tab correct. But I can still see the 4 tabs (headers) instead of 2.
When I tried click on the second tab - the second tab links just popped up above the frist tabs links.
Is it not compatible with 3.3.1 or does it have any problems in their functions?