[Exim] redirecting e-mails for local domains to another smtp…

hi.
i have exim 4.05, and little problem.

i'm sending e-mails via exim's command line, exim is not running as
daemon. all i want is filter, that checks the recipient,
if it has a domain name that is the local domain, then
redirects message to another smtp running on some port as daemon.
ofcourse if the recipient doesn't have domain name that matches with
local domains, then the mail is send via remote_smtp.

don't ask my 'why? what for?'
i know that this is silly. but i exactly know what i want do
but i don't know how.

please help.
sorry for my english

Lukasz