MMAIL acting really weird

["James H. H. Lampert" <jamesl@xxxxxxxxxxxxxxxxx>]

I just did a test run on our new invoice system, which uses Perotti's 
MMAIL, and the BCC addresses are appearing in the copy sent to the "TO" 
address.

I then tried calling the relevant MMAIL command from the command line, 
and when I did

SENDMIME SUBJECT('I like Spam')
 SENDER('James Lampert' JAMESL@xxxxxxxxxxxxxxxxx)
 RECEIVER((*TO 'James Lampert' 'jamesl@xxxxxxxxxxxxxxxxx')
          (*BCC BCC 'jamesl@xxxxxxxxxx'))
 ATTACH((*TEXT *BODY 'text/plain' '/foo.txt' *SAME *N *N))

the copy that arrived at jamesl@xxxxxxxxxxxxxxxxx looked like:
> Date: Tue, 04 Jun 2013 15:50:13 -0700
> From: James Lampert <JAMESL@xxxxxxxxxxxxxxxxx>
> To:  James Lampert <jamesl@xxxxxxxxxxxxxxxxx>
> Bcc: BCC <jamesl@xxxxxxxxxx>
> Subject: I like Spam
>
> This is a sample of the work done on this machine.

What could be doing this, and how would I fix it?

>>> The plot thickens:

When I use my personal email address (the one at Quik Internet of 
Huntington Beach) for the "To" address, this doesn't happen. But if I 
use my personal GMail address for the "To" address, it DOES. Currently, 
all touchtonecorp.com addresses are handled by GMail.

It appears that GMAIL is somehow failing to hide the BCC, when the 
message is sent from MMAIL, and the TO recipient is a GMAIL address. But 
further tests show that this only seems to happen when sending out of MMAIL.

Which brings me right back to what could be going wrong, and how do I 
fix it?

--
JHHL