[Dovecot] Email filters

[Jos Chrispijn]

Can someone tell me how I can configure Dovecot to use message filters 
on incoming email?
When I now activate my mail account on my mobile phone and Thunderbird 
(or any other mail client with message filters) is not online, I get a 
huge pile of email in my INBOX that I have to go thru, while 90% is not 
that interesting to read as they belong to Spam messages, newsletters etc.

Thanks in advance
Jos Chrispijn