Ok, I reconfigured the network to static ip:

Interface Name: eth0, type: 1

Tags:
Device: DEVS:Networks/sungem_eth.device
Unit: 0
DoOnline: True
IPAddr: 192.168.0.254
Netmask: 255.255.255.0
Gateway: 192.168.0.1

192.168.0.1 is my router.
192.168.0.254 is definetly unused by another computer (pinged it under windows)

No reaction @all. Can't ping router. No Connection, but again the router led is green on the used port. o.O