+DSN: processing router : r1
+DSN: processing successful delivery address: 2@b
+DSN: Sender_address: x@y
+DSN: orcpt: NULL flags: 0
+DSN: envid: NULL ret: 0
+DSN: Final recipient: 2@b
+DSN: Remote SMTP server supports DSN: 0
+DSN: not sending DSN success message