I have a 2910 and 2820 with IPSec VPN established between the two routers and all works fine for local users on each subnet. The 2910 is on 192.168.2.0. the 2820 is on 192.168.1.0.
If I VPN in as a Dial-in user on the 2820 using PPTP, I get an IP address in the 192.168.1.0. range as expected and can see the local network but not the other end (2910) of the VPN tunnel.

The Dial-in user is connecting via a public IP address on the 2nd Subnet.

It sounds like a routing issue but not sure how to go about settting it up.
Thanks

I do not use it, but does the SmartVPN client allow you to set up extra subnets for the tunnel?

The other option is to set up the routing in the road warrior. Have a look at the "route" command for the road warrior. You would need to route all 192.168.2.0/24 traffic via 192.168.1.1.

An alternative would be to set up another VPN from the road warrior directly to the 2910.

I'm only using the VPN client in Windows XP Pro, perhaps a third party client might be more flexible.
The 2910 has a dynamic IP, the 2820 static, hence dialing into the 2820.
Will investigate Drayteks own VPN client.

FWIW, Draytek's VPN client is only a front end for the Windoze client. I can't remember but can you put in an FQDN instead of IP address in the Windoze client? If you can, register the 2910 with a dynamic DNS provider (DtDNS is my preferred one). You can then set up a VPN to it.