+
+++ Recieved-by header tracking info
+++ - WITH protocol types get UTF8 prefix
+++ - use for logging also
+
+forwarding checks rfc6530 7.1 -3-
+- rcpt-time rejects get 533 mailbox name not allowed
+- mail-time rejects get 550 mailbox unavailable
+- bounces (see dsn handling)
+
+flag in spool file
+
+++ expansions for to- and from-Alabel ? bug1567
+
+enhanced status codes? rfc5248++
+
+VRFY
+EXPN
+
+non-smtp input