[MM3-users] List in list, mutiple reply-to addresses

Dear List,

we habe observerd the following behavior, when a list is member of another list, the reply-to-address has multiple entires:

list iu-all@mydomain member: iu-int@mydomain

list iu-int@mydomain member: john@mydomain

Case)

Sender: mike@mydomain To: iu-all@mydomain

john receives following mail:

from: iu-int@mydomain
reply-to: mike@mydomain, iu-all@mydomain

If john now hits reply in mailclient, mail goes to ALL instead of just the from-address, as mailman extended the reply-to header.

How can this be changed?

thank you.

Stefan