[Mailman-Users] subscribe another list as a member

[Hong Jiang Tian]

Hi,

There were two mailing lists of lista and listb on the Mailman server. I
created a new mailing list named listc by subscribing lista and listb as the
only two members of listc. When I posted to listc by a member of lista, the
mail was being held until the list moderator can reviewed it for approval.
The reason it was being held: Post by non-member to a members-only list. 

My question: 
Is it possible to subscribe another list as a member of the current list
with Mailman?

Thanks for your help!
Hong