Aaron,
I like where you going with this. You are correct the server that sets the cookie is always the primary server. I am only concerned about one issue of your purposed solution and maybe that it's not an issue at all and I just am not fully understanding what you mean by mapping. I am assuming that you are meaning hard code the ip:port to a corresponding hash value in the i-rule. If this is the case for some reason if you reboot, restart or shutdown the bea services this hash value changes. Now why I'm not exactly sure, I would think that the hash would be the same as long as the value it's hashing does not change, but this is not the case.
If you could show me a rough draft that would be excellent.
Thank you for you support.
-Brett