Routing problem or Gateway Issue?

[mynus]

I'm using two 506E's for a site to site tunnel between our two networks. Here's an example:

Site1: 192.168.1.X
Site2: 192.168.2.X
Pix1 Outside: 172.100.100.1
Pix1 Inside: 192.168.1.1
Pix2 Outside: 172.101.101.1
Pix2 Inside: 192.168.2.1

Site1---[Pix1]....(VPN)....[Pix2]---Site2

Both sites are accesible via the tunnel (for the most part), and both sites are using NAT for the hosts that are getting internet access through their respective pix's. At both sites we have dual gateways, from different mediums and providers, and going in totally different directions. I'm not terribly new to Pix boxes or anything, but thise is the first time I've had to deal with multiple gateways.

So here's the problem. If hosts inside either of the sites aren't pointing at their Pix as a gateway, I can't see them through the VPN. I can ping them through the Inside interface back into their own networks, but that's it. Even if I connect to the Pix with the VPN client, same issue, so I know it's not a mis-configuration. This is some standard policy on how the device works. Is there any way around this? Like putting another router behind the Pix's to move traffic around the internal network?

 

[NetworkGhost]

Looks like a routing issue. Whatever there current gateway is when it is not the pix would need to have a route for the destination VPN network pointing torward the pix to route traffic. The default gateway is where a device sends traffic that is not destined for the immediate subnet and also has no other route. The gateway needs to be able to route that traffic in the appropriate direction.