migrating from GroupWise to Exchange. Have all working, except for one issue:

When a user from the exchange system sends an e-mail to a user in the groupwise system (through the connector) and in the same message includes addresses of users on the internet, the message is send out to everybody just fine. But, when the groupwise user wants to "Reply to All", it is only send back to the Exchange user and not to the users on the internet. Reviewing the message from the groupwise user's mailbox shows us that the internet users are in the message in the following format:


Where APIGW is the name of the API gateway in the groupwise system and GWDOM is the name if the GroupWise domain where the API resides.

Any ideas?