What I did was create a node for the IP of the my first hop passed the last node I own and set it to icmp only. Then ensured my routing would only go the way I need (static routes so nothing re-routes it around to come from the other side).
Thanks for the tip, mate!
Actually I had tought about doing something like this, but the problem is that I have a few dynamic IPs on the ISPs (xDLS, PPPoE, DHCP Cable Modens, etc).
For sure this is a solution for my static internet IPs, but I am looking for a solution that covers my entire network (we're talking about 200 gateways, 600 links).
Thanks a lot anyway,