3. Change company policy to reflect names like xx.yy@us.groupname.com, xx.yy@uk.groupname.com, etc, where DNS would resolve to the correct server. Doesn't give corporate the "email image" they are after.
unfortunately, all public routing to email servers is based only on domain names, so the domain name has to contain differential information if differential routing is needed.
In his case, it sounds like he actually has a business case for solution 3 above. It only requires putting a dollar figure on the cost of losing the partner relationship and some risk percentages based on his own company being unreliable and a pain in the rear to work with. That should allow him to set up the infrastructure which allows critical workers (such as engineers exchanging CAD files) to use the region-specific addresses. --Michael Dillon