side-2-side ipsec with multiple subnets

Hi,

I have a problem connecting a ipsec tunnel to a draytek Router with multiple subnets in the remote side.

my side (192.168.222.x/24) - ASG220 (V8.3) => ipsec tunnel => Draytek (192.168.25.0/24) => 2. Drayrek (10.3.10/24)

So my option is to configure the 192.168.25.0 and 10.3.1.0 as remote networks and my 192.168.222.0 as internal network.
If I do that the phase 2 is only established for the 192.168.25.0 network.

The draytek routers are controlled by a different men. He says I have to route the 10.3.1.0 network through the tunnel.
Is that right?

I thought that I have to configure every subnet in the ipsec tunnel. Or is it possible to route other subnets through the ipsec tunnel?

And how I have to do this (if it is possible)?

Many thanks!