We are developing a non-delivery reports analyzer for Sympa MLM.
This module already extracts bouncing address and error status for more
than 90% of "bounces". The goal is to provide information about
bouncing addresses within a web interface (WWSympa) for list-owners.
Analysis is mainly based on RFCs 1891-1894 defining a MIME extension
for Delivery Status Notifications, allowing (automatic) identification
of recipients and error status.
RFC 1893 defines Mail System Status Codes to be used by MTAs.
Eg: 5.1.1 => User unknown ; 5.2.2 => Mailbox full
I found out that aol.com is not compatible with status codes as
defined in RFC 1893. As you can see in the sample bellow, the
transcript of session indicates a 'User Unkown' whereas "Status"
field of the delivery-status indicates a Success (2.0.0). This
completely alter the analysis of error reports !
Did anyone already observe such problems with other ISPs ?
Here is a sample Delivery Status Notification :
Content-Type: multipart/report; report-type=delivery-status;
----- Transcript of session follows -----
... while talking to xxx.mail.aol.com.:
>>> RCPT To:
<<< 550 MAILBOX NOT FOUND
550 ... User unknown
Reporting-MTA: dns; listes.cru.fr
Arrival-Date: Thu, 6 Jan 2000 09:22:43 +0100 (MET)
Final-Recipient: rfc822; email@example.com.
Diagnostic-Code: smtp; 250 OK