[Mailman-Users] question about members on several lists

[Sandi Gruver]

Members on List A and on List B only receive one copy of a message posted to both lists.
They want to know why.

Somewhere, awhile ago I found that this is a Microsoft Outlook 'feature' owing to the lack of message numbering in Mailman, but I searched the Mailman archives this afternoon without success in finding any documentation on the reason this happens. 
Any ideas where this is?
 
(We happily run Mailman 2.1.5.1 on RedHat Linux)


Thank you,

S Gruver
Unix System Administrator
SBCTC-IT