[Dovecot] Deliver limit based of number of destination recipients and size of mails, any option to do that?

[Andrés Yacopino]

I have a mail server with postfix, dovecot (1.2.15) and deliver lda
(dovecot) with 350 users.
I have the problem that in this christmas the employees are sending some
big files (mainly powerpoints files) to a lot of recipients, because of
that the server get a lot of charge (is a Xeon quad core 5405 with 4GB
of Ram), i have four disks in Raid 5 configuration (HP E200 controller,
not very fast)
Is there any option to limit this type of delivery, the total size of
the mails delivered to each user (total recipients * size of mail), in
dovecot deliver.
I don't want to limit the concurrent delivery more lower than 350
recipients and the max size of the mail we can send is 15M.
Thanks a lot,


-- 

Andrés Fernando Yacopino