[exim] help with old spam messages

Hello!
I want to regejct messages older then specific time and date.
I found this solution
http://www.exim-users.org/forums/showthread.php?t=55470, but it
rrequires external cript to run. I think that exim can do this
internaly, can You help me?

--
Vasiliy Tolstov <v.tolstov@???>
Selfip.Ru