POPing a server in Mailman

I am trying to solve a simple problem that Mailman has created with some corporate email systems. The normal handoff that Mailman does to the mailserver shows a handoff from 127.0.0.1 from localhost@localdomain. Many servers block these messages thinking they are SPAM.

My thoughts are to POP the server whenever the mesage does not go through. I know it works - I can manually pop and then the mail goes through using the actual IP and servername. I just cannot figure out exactly how to put the code in. I would think it goes in where the SMTP exception is - but I need it to restart the message and not drop it.

The entire souce code for Mailman, if needed, is at URL.

Thanks in advance.

Some same code from oreilly that pops is attached also.