[Fedora-xen] Network Problem after todays update

[Sven Oehme]

Hi , 

i did an update today from kernel-xen-2.6.18-1.2869.fc6 to 
kernel-xen-2.6.19-1.2895.fc6 and from xen-3.0.3-1.fc6 to xen-3.0.3-3.fc6 .
the upgrade itself went fine, and all on dom_0 works as expected.
But i have now trouble with my guetsts Network. All guests are connecting 
to the outside world over NAT.
i can ssh between all guests as well as between dom_0 and all guests.
i can ping each box outside the dom_0 (my dns server for insteance) but i 
can't ssh or ftp to any box outside my internal dom_0 network, it always 
timed out.
looking at a tcp dump it marks the frames i send from the guests as 
Checksum Errors.

any ideas ? should i open a bugzilla entry for this ?

Sven