501 Syntax error: Empty email address.

[Rolando Guaracio]

Hi,

I have the following situation.
When my internal postfix MTA send a NDN it send it with null from 
(from<>). Next, this message is send to the external postfix MTA to send 
it to the Internet. The problem is that this message is bounced with the 
following line: said: 501 Syntax error: Empty email address. (in reply 
to MAIL FROM command)).

What can I do?

Thanking in advance.
Best regards.

Rolando.