[PROBLEM] Fresh Install (XBian_1.0_RC_2) no Ethernet

[Chandalan]

I've installed XBian_1.0_RC_2 on my freshly new Raspberry 512MB. Iam seeing the xbian-screen on my tv, but the ethernet port is not working as I can see it on my router-web-dashboard.

I've no idea what could be wrong. Iam using an old raspberry (256mb B-Modell) since years and never had a problem with a new install or anything else.

Can anybody help me?
Right now Iam neither able to connect by ssh nor using yatse remote from my smartphone, so I cant post any logs or config-Files.

I also tried it with my wlan-dongle, but also.. no network connection

Thanks in Advance for any help and
apologize my horrible English, its not my mothers tongue!