The IETF specs say that usernames should be no more than 64 characters, and a domain name should be no more than 255 characters.    So when I created database tables for logging email addresses, I used a column size of 320 characters.   Recently, I have discovered that this size is not capturing complete data, because some ads have very long reply-to addresses.   The longest in my archive is 317 characters.   I wonder what SmarterMail would do if someone tried to reply to one of those messages.

I am feeling increasingly hostile toward unsolicited advertising, so I think I will create a filtering rule to discard messages that violate the standard so severely.   Don't know what boundary I will use, probably more than 64 characters, but much less than 317.