L2TP/IPSec VPN route pushing?

Hello,

I've got a 'road warrior' set up working into my ASG 8.300 using L2TP/IPSec. My VPN IP pool is 192.168.243.0/24, and my internal LAN is 172.16.1.0/24. I'm using the built-in Windows 7 VPN client.

When I connect, the client is assigned 192.168.243.2 with a gateway of 192.168.243.1. That's fine, I can ping the gateway (I've configured the necessary rule in the ASG firewall).

In order to get to my internal LAN, I need to add a route to the Win7 client PC as follows:

"route ADD 172.16.1.0 MASK 255.255.255.0 192.168.243.1"

Once I've done that my road-warrior client can access devices on the internal LAN. All well and good. When I disconnect the VPN client, however, the route to 172.16.1.0/24 is removed.

My question is whether there's a smart way to automate the addition of the manual route after I connect the VPN. I've seen mention of "route push" but only in relation to OpenVPN connections. As I'm doing L2TP/IPSec, I wonder if this isn't possible and I have to use some sort of script in the client.

Has anyone achieved this?

Thanks,
Giles.