🚀 go-pugleaf

And unless i miss my guess (tested this on Sendmail on RedHat 5.2),
the default install always responds with a 250 OK, even if the
address is not valid. So does our ISP (8.8.7, 8.9.1 respectively).

In fact, of the 3 mail servers on which I am _allowed_ to
play on, none of them will provide userid existence acknowledgement
in real-time.

Cheers, Thomas

Tollef Fog Heen wrote:
> 
> distler@golem.ph.utexas.edu (Jacques Distler) writes:
> 
> > There's no way to disable *that* without breaking SMTP (which is why only
> > a bozo would disable VRFY).
> 
> There was a discussion regarding this on bugtraq some time ago, where
> spammers had used exactly this method of gathering addresses. Also,
> note RFC 1123:
> 
>       5.2.7  RCPT Command: RFC-821 Section 4.1.1
> 
>          A host that supports a receiver-SMTP MUST support the reserved
>          mailbox "Postmaster".
> 
>          The receiver-SMTP MAY verify RCPT parameters as they arrive;
>          however, RCPT responses MUST NOT be delayed beyond a reasonable
>          time (see Section 5.3.2).
> 
>          Therefore, a "250 OK" response to a RCPT does not necessarily
>          imply that the delivery address(es) are valid.  Errors found
>          after message acceptance will be reported by mailing a
>          notification message to an appropriate address (see Section
>          5.3.3).
> 
> So you can't be _sure_.
> 
> --
> 
> Tollef Fog Heen
> Unix _IS_ user friendly... It's just selective about who its friends are.