Clone, what does it do technically in an iRule?

Yes, I have an email relay in an adjoining DMZ to the F5 that I can use. I also mentioned in my original post about possibly using a sideband connection but we just upgraded to 10.2.4 HF5 over the weekend so I do not think it is available to me.

Also, if I am understanding you correctly about L2/mac re-write issue, the IIS server has an IP Binding for the IP address I have assigned -- but the traffic coming to that server has the original destination IP still in it from a higher layer so the IIS servers TCP stack is discarding it instead of accepting it as a valid request.