network stops after starting browser in 3.6

Internet browsing stops after displaying the first page - using the PC-Welt 3.7. Testing 3.6 the same result.
After a reboot pinging my router (10.0.0.138), myself 127.. or ..154), www.google: everything OK.
Start Konqerer - Ping stops.
Brought down and up eth0. pump also just hangs.

I have used the 64bit version on my AMD64 (http://www.applia.fr/contents/knoppix64.html) - NO problem.

Any ideas?

Freek Boersma
MSI K8TNeo /AMD64 / 3xSATA / Realtek 8139 eth0 / SMC eth1