About null sender

[Ralf Hildebrandt]

* Feel Zhou <feelzhou at gmail.com>:
> Hello, my friend
> 
> This is Tom, I'm sending my greeting from China
> I have some problem with my mail server, and I need your help
> I have install postfix+amavisd+clamav+spamassassin in my mail server

> My customer send mail via my mail server, It's working very well
> For now, always have these log file
> May  9 17:26:18 amavis[3938]: (03938-14) Passed CLEAN, [IP1] [IP2] <> -> <someone at example.com>,

> How can I make all this null sender mail as a spam email, and then it will
> be blocked

Why would you want to do that? These are non-delivery messages. If you
suppress them, your customer won't know that his mails didn't reach
the recipient!

-- 
Ralf Hildebrandt                   Charite Universitätsmedizin Berlin
ralf.hildebrandt at charite.de        Campus Benjamin Franklin
http://www.charite.de              Hindenburgdamm 30, 12203 Berlin
Geschäftsbereich IT, Abt. Netzwerk fon: +49-30-450.570.155