>I'm still confused why binary data is allowed apass to exceed the limit >defined in RFC 5321 4.5.3.1.6.
I dunno, but RFC 2045 §2.9 is clear on this subject. I suspect that they do not consider binary data to be a "text line". It is not clear to me how successful it would actually be if you sent binary data "in the wild". It also might be that limit only applies to the SMTP protocol itself and NOT what appears inside of a DATA command, as it says that limit may be extended by a SMTP Security Extension. Also, I found this nugget from RFC 5321 §3.3: When the RFC 822 format ([28], [4]) is being used, the mail data include the header fields such as those named Date, Subject, To, Cc, and From. Server SMTP systems SHOULD NOT reject messages based on perceived defects in the RFC 822 or MIME (RFC 2045 [21]) message header section or message body. Dang. --Ken
