[Calderon]

Thanks.

Tried with rc.local but didn't seem to get it working.

Eventually i managed to find this which seems to be working.

Change your dhclient.conf file so that it doesn't 
request 'routers' (for that interface) and set the default statically by setting defaultroute in rc.conf.

dhclient.conf without requiring routers.

reject 192.168.0.254;
interface "bfe0" {
         request subnet-mask, broadcast-address, time-offset,
                 domain-name, domain-name-servers, host-name;
    require subnet-mask, domain-name-servers;
}

Also there´s sometimes popping false configured DHCP's on the University network so that's why the reject.

BTW can i put some IP range to the reject?