Script needed

hi guys!

i need a shell or perl script which wud keep recent certain number of mails(say last 4 mails) from
mailbox of a mail user account and delete all other older mails from its mailbox.I m using linux enterprise server
and have user mailboxes in /var/mail/* .Does anyone of u have such a shell or perlscript which wud serve tht purpose?
help will b appreciated .
thnx

shahzad

OK I'll bite. Why would you want to delete all emails except for the last 4 ?

And what is "linux enterprise server" ?

our mail users often request cleaning of their mail boxes in such a way tht they want mails prior to certain number of their mails whus b delete.
4 is just an example....script wud b customizable so tht i can customize it according to mailusers request. mail server keeps unnecessary mails which overloads it...thts y i wana make it as light as possible..
shaz