General routing

I work for a small IT consultancy and we have recently been experimenting with remote support via ISDN routers rather than dial up modem.

This has given us a problem as many of our clients have the same IP address ranges (ie: 192.168.0.1 – 192.168.0.255) and also the same server names.

Is there anyway that we can configure a routing solution that doesn’t involve actually changing client networks (esp as some may not wish to be changed !)

I thought maybe some kind of virtual network in between but to be honest whilst I’m learning fast about IP and routing, it’s still out of my depth.

It would be really great if someone could help me out on this one !

Thanks
Steve