Routing a recipient (Transport Agent)

Hi

I have an unusual situation. I have a Exchange hosting a domain call it example.com, if sender@example.com sends to recep1@example.com and recep2@example.com or just recep1@example.com I just need to send recep1@example.com to another SMTP Server outside of the Exchange enviroment.

Now the only way I can think of achieving this process is with the use of transport agents, but I not sure on which part of the transport agent framework I should be hooking into to do this.

I'm running Exchange 2010 SP2.