On Mon, Jun 27, 2005 at 06:07:03PM +0100, Mark Smith wrote:
> We don't generate bounces to external senders, only local senders, and we
> only do that because some MUAs don't cope well with rejections at SMTP time.
Your ACLs can easily be set to identify MUA traffic from MTA. Traffic
coming from local address space can be presumed to be MUA. Internal
mail servers can be identified by hardcoded list or SMTP AUTH.
External MUA are identified by SMTP AUTH since that is likely part
of your existing anti-relay mechanism.
Then it is a simple matter of rejecting at SMTP time for MTA and
generating bounces for MUA.
This generally will also reduce the size of your queue runs since
you will have far fewer bounce deliveries due to misaddressed spam, etc.
