I have had this same problem since I installed Karmic. I would say a majority of the time when I login the NetworkManager applet is replaced with the black box. I just remove the "Notification" panel and re-add and that fixes it.
-- nm-applet shows as unresponsive black box https://bugs.launchpad.net/bugs/444333 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs