I think this problem is due to the server not having a route back to the VPN pool IP address range.
Remember, when the remote VPN client connects he gets an IP address from the local ISP and when the VPN tunnel comes up he gets another address that you have configured in the IP pool statement. So either your server needs to be able to route to that address range, either using a static route, or via your default gateway.
The 8 bit subnet, do you mean 255.0.0.0 or 255.255.255.0 ? Either way I'd initially suspect classful routing somewhere, where do you see this address?
Andy
Andy