Version:            (using KDE 4.4.2)
OS:                Linux
Installed from:    openSUSE RPMs

I run Opensuse 11.2 (x86_64) with KDE 4.4.2 with latest Updates from Suse's factory Repository. X11 and SSH packages are updated, too. 

Since one of my last KDE updates I can no longer start any KDE applications on a remote system which I access via ssh. At least not as a standard user. This is true for any KDE applications that need D-BUS. A command sequence like   

> ssh -X user@remote-machine
password:
> dolphin & 

fails with 

<unknown program name>(7021)/: KUniqueApplication: Cannot find the D-Bus session server:  "Failed to connect to socket /tmp/dbus-3XY1ugf0q0: Verbindungsaufbau abgelehnt" 

<unknown program name>(7018)/: KUniqueApplication: Pipe closed unexpectedly

However, when I type 

> dbus-launch dolphin & 

on the remote system everything works as expected. 

Also, no problem when "root" connects to the remote system via ssh and starts KDE applications. For root it works. So it may have to do with policy and rights and/or an auto-launch problem of d-bus. For standard X-applications as xterm there is no problem. 

D-Bus is running on my system and the remote system. In my ~-directory there is the needed file in ~/.dbus/session-dbus. 

I have a comparable Opensuse 11.2/KDE 4.4.2 installation on a laptop which I have updated at the end of Feb 2010. There everything works normally. Therefore, I am quite sure that the strange behaviour came with some of the latest KDE, X11 or SSH updates.