False error when not connecting to SMTP server

We have been using 360Works Email Plugin for several years to great success. The grad school recruiting team sends messages to admitted students that include both standard and custom-created PDF letters as attachments. The email script runs in the FMP client machine and we are using a special SMTP server address alias reserved for automated mail messages from on campus devices. This has worked well from both wired and wireless clients until the campus network managers started using NAT-addresses for wifi clients. Now we discover that a machine on the wifi network cannot reach the designated SMTP server address, but the Email Plugin error message says that the email addresses are invalid, rather than complaining about not connecting to the SMTP server. We can get the connection failure message by changing the EmailConnectSMTP entry to a bad address.

Fortunately, we have other SMTP servers to use which will work with wifi users. But we chased the wrong error for so long, I thought I should report this.

Gary