ifconfig caused server/network crash

I just got a second IP address for my Debian Squeeze root. I tried to add the address to my network but somehow I messed up. The command I executed: ifconfig eth0 [new ip address] mask 255.255.255.254

Now, I cant get any response from the server e.g. apache, ftp etc.

I did not try to restart it yet. Is there any possibility to fix this?

Thanks in advance!