Mailpost and crosspost

[Mailing Manager]

Hi all,
    i've a working installation of inn 2.4.0 and i want to use mailpost for
receive mail for some alias and post to the right group.
Now it is working well, but for one group at once!
For me it is necessary to allow the crospposting:

alias1 is group1
alias2 is group2

The same mail would be sent to both alias1 and alias2 and i need to see them
on both the groups.
I used the -c parameter but is seems to be good for to sleep, but only for
that purpose...

It is possible to allow crosspost with mailpost?

Thanks

Michele