Internet connection single interface through vpn

Hi.

Can you please help me with a routing problem?

There are 2 networks:

192.168.10.0/24 (eth0)
192.168.11.0/24 (eth0:1)

The default gateway is 192.168.10.1
iPv4 routing is already enabled and working.

With vpnc I've built up an VPN connection and can access my home network (192.168.0.0/24) about the tun0 interface.

I want to leave the default gateway from 192.168.10.0/24 unchanged, but I want access the whole internet traffic vom 192.168.11.0/24 trough the VPN connection.

Unfortunately I don't get ideas in my head how I could solve this problem.

Thanks for your help and Merry Christmas

regards