>
> I want to limit mail sizes for both incoming and outgoing mails.
>
> Let's say
>
> userx@example.com <mailto:userx@example.com> can send mails up to 5MB,
> but can receive up to 2MB
>
> usery@example.com <mailto:usery@example.com> can send and receive mails
> up to 5MB.

Is this 2/5MB after encoding or before encoding of attachments? Encoding
will increase data size about 25%.

> pls let me know?

mimedefang? You have per user settings and so setting a system wide
setting in sendmail configuration will not help and sendmail does not
differentiate between outgoing and incoming limits so you are left with
a milter solution and so maybe mimedefang is your best bet.

I know another centos list subscriber, Les, will swear by mimedefang.