How to relay only messages from system users?

I use exim for mail server.

[boska]

Do you know haw to accept to send messages only from user that is registeres on system?
I use EXIM for mail server.

[DaveAtIFG]

Welcome to WebmasterWorld boska!

Are there any Exim users lurking about that can help boska set up his server? :)

I'm sure you've found the Exim docs here [exim.org]. Support is offered through their exim-users mailing list if no one here offers help.