Internal E-mail Routed Out to the Internet

[dpuller]

GW7.0.3 system

Issue became evident when a 3rd party encryption solution was implemented. When an external contact sends an e-mail to multiple internal mailboxes in our GW system and one of the internal recipients replies to all, even the replies going to the other internal addresses must go out to the internet. The problem appears to be that the format used by the external sender is <userid@domain> and because of the <> it is not recognized as an internal address. Unfortunately that means that e-mail that would otherwise stay internal to our GW system is going out to the internet and in the case of HIPAA content, it is unnecessarily encrypted.

Is there any way that GWIA can recognize the internal address within the <>'S so internal messages stay internal?

Thanks in advance for any insight!