[Dovecot] How to archive mails on different server

[Anant Saraswat]

Hi Guys,

I want to make some new changes to my exim mail server So if any user 
archive his/her mail they will save on any other server not on Exim 
server , and whenever user want to search for any old mail he will go to 
archive folder and can search it from there.... So basically i want to 
setup a diffrent server for archiving and want to connect it to my Exim 
server. So whevever user archive his/her mail it will autometically save 
to diffrent server.

So is it possible using any plugin , or something else . I am using 
Roundcube,Exim 4.72, Dovecot(LMTP).

Regards,
Anant Saraswat