Ok solved it now, by entering an IP adress within the DHCP range of my server (which I did already but didnt work then) and leave it in AUTO mode.
The important thing is maybe to set it up without being connected to the Untangle Server. So I started the AirStation, plugged my Notebook in, entered the LAN IP adress 192.168.1.100, disabled DHCP and waited for restart. I tested if it's reachable by giving my Notebook an IP manually (f.e. 192.168.1.164) got access to the Web Interface.
Then I plugged the AirStation to my Server and now I can reach it via its IP and my devices have their old IP's back 192.168.1.100-200.
Important: Unplug AirStation from network, leave it on AUTO so it doesnt not use 192.168.11.1 as IP and enter the IP manually, disable DHCP (of course lol) and plug in again.
Easy, but even though I did this before it didnt seem to work first. Now I'm happy.
Message Edited by rikh64 on 02-14-2009 02:50 AM