[44net] tunl0

Hello, While waiting for my allocation to be actioned and having little or no experience I decided to experiment to learn more about the use of the tunnel interface and what would be possible with it. I have all ports forwarded from my ISP's modem to a PC I am using as a router. I have a tunnel set up on a one to one basis with a forwarding partner and it works well. My router PC has three network cards, one with a 192.x.x.x/24 address and the other two with a 44.x.x.x/29 and 44.x.x.x/27 address. Connections between both 44.x.x.x addresses work with my forwarding partner and I can forward between my 44.x.x.x addresses using [ eth0 ] but not when I set the route at each via [ tunl0 ]. Is it something simple I have missed ?? Regards, Ian..