OpenVPN - routing WAN port forwarded connections through VPN

I have an iOS device with OpenVPN installed and set up the Toastman VPN tomato build on my E3000 to allow OpenVPN connections such that all VPN traffic gets routed through the VPN. That works fine for Internet traffic, but it doesn't work if I attempt to connect to a WAN side port forwarded port.

For example, I have a port forwarded to an internal machine on my network. If I access that port on the WAN, it bypasses the VPN and makes a direct connection to the port.

I know I could just...

OpenVPN - routing WAN port forwarded connections through VPN