I need to share an SMTP namespace on Lotus so that unresolved recipients which exist on an Exchange 2007 server in the same domain are routed there. Routing from Exhange 2007 to Notes is easy and this works but I can't fathom how to make Lotus share it's SMTP Namespace. Many articles talk about using exchange.domain.com and domino.domain.com which does work, but this is not useful in our scenario when we need to keep the same SMTP domain on both systems - sure a comman situation that someone must have done during a co-existence exercise. Various posts hint at it being possible but no information is available.
Have you looked at the MS and IBM tools for synching Exchange and Domino ?
These tools may provide an answer for you.
I hope this helps !