[Exim] local domains only...

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Hello.

I have a question, how do I "lock" exim so only specific domain's are alowed to be used as outgoing mail.
For example, on my server I have these domains added reboot.nu and gangster.to, but people can send mail
thru my exim server with asd@???. I want to lock exim to only allow outgoing mail to
be xxx@??? or xxx@???. Annyone who can help me?


//Jonas

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