Zypper aseertion error

Hi
When I use zypper for updating or installing software I always get this kind of error :
GLib-GIO:ERROR:gdbusconnection.c:2279:initable_init: assertion failed: (connection->initialization_error == NULL)
between the retrieving processes.

su
# zypper refresh

Write the output here.

And also read this http://linux.derkeiler.com/Mailing-Lists/SuSE/2011-03/msg00259.html