Comment 1 for bug 370438

Same problems as you.
The only way out of it seems only restarting totally X. If you kill directly the daemon will kill also the desktop manager.
At the moment I seem to have some fortune (the daemon is stable for me in the last couple of hours at 84m), if I stop using opera as browser (I switch back to firefox, just for testing). I had notice that, if i keep loading different pictures with opera the dbus-daemon memory count keep increasing....
On the other point, I have search on different posts for linux and we are one of the few with this problem with ubuntu (or Kubuntu for me) Jaunty. We both did an update and we both use opera as a browser (not too common).
I will test my system running firefox for some day and put an update.