[KDE 4.7]Rekonq and Dolphin launchers stay always on task manager in panel after restart

I need to know if this problem happens to someone to be reported as a bug.
This problem occurs on Kubuntu 11.10 Oneiric Ocelot. The Rekonq and Dolphin launchers are on the task manager on panel. Clicking on them opens the program and launchers disappear. You can also remove them with the right mouse button and "Remove this Launcher". But when the system is restarted, the launchers coming back. I have selected "Start with an empty session" from SystemSettings.
When upgrading to KDE 4.7 in Natty from Kubuntu Backports PPA did not have the same problem. But if I remove the panel and add a Default Panel I get the same problem with launchers.

Edit:
Seems to be a KDE bug, I found this:
https://bbs.archlinux.org/viewtopic.php?id=123833