Applications :: Routing Applications Through Specific Connections

'lo i use a iMac mid '09 @ work we have access to multiple connections Ethernet and Airport. Sadly the Ethernet is fire-walled and doesn't allow specific connections through; lucky though the airport is not.
The thing that is most frustrating is our system critical app HAS to run through the Ethernet to function under the fire-walled connection; but being on mac it's a friggin task to switch between the two because you have to go into network and set the service order each time to flip between them. I really need away that i can assign a specific application to use a specific connection (airport) that is active and connected while keeping the service order the same as to not mess with the system critical App that has to run through the enet. Is there any process or outside app that i could use to force other apps to use the airport connection while still leaving the Crit app using the enet?

I've been able to set the service order over to airport launch the app i want to use it and then switch back over to enet for the crit app but it seemed to work fine but that's a lot of Jank to pull each time i want to use an outside app. also i didn't really do it for any length of time so i don't know if that process would even hold up over time or flip back over to the opposite connection when it needed a fresh link