Change domain in fetchmail

I have the server name mail.domain.com  which comects to the ISP only
when required.

On the internet I have domain.com as an address and the mail is sent to
domain.com but when I retrive it with fetchmail it can not resolve
user(_at_)domain(_dot_)com to user(_at_)mail(_dot_)domain(_dot_)com  my 
.fetchmailcf is

poll mail.isp.net
       protocol pop3
       username name
       password word
       localdomains mail.domail.com
       is * here