Reformatting 'To:' line in mail headers

[tulio @ Ahip . Getty . EDU (Tulio Hernandez)]

I am trying to reformat the 'To:' line in the mail header so
that when the messages are resend to the list of users it displays
something like "To: Multiple recipients of list-name". How can
I accomplish this? 

I am not sure of this is a function of Majordomo or the
aliases in the /etc/aliases file. I am using Sun OS 4.1.3 with
sendmail.mx and majordomo 1.92.

Thanks,

Tulio
tulio@ahip.getty.edu