It appears that PHPMailer and DokuWiki's mail_send() functions differ as follows: - PHPMailer does not first validate email addresses as DokuWiki does. Instead it delegates address validation to the SMTP server and reports invalid addresses. I'm inclined to apply DokuWiki's validation before handing off to PHPMailer. - Multiple recipients are only comma-separated in PHPMailer, whereas DokuWiki puts each recipient on its own line "to avoid too long headers." If I try to sneak returns in they might get encoded. - PHPMailer does its own text encoding. PHPMailer auto-chooses among several different encodings, while DokuWiki always uses "quoted printable." PHPMailer's quoted printable encoding appears simplistic by comparison to DokuWiki's. - PHPMailer has different error messages from DokuWiki and does not provide a standard code that I might use to translate them into DokuWiki error messages; what you get is language-specific. However, I might reverse-translate a few important error messages. - DokuWiki's mail_send() allows the caller to pass in raw header text for inclusion in the message header, but PHPMailer does not appear to support this. In PHPMailer you have to name each header separately. DokuWiki does not currently take advantage of this mail_send() parameter, but my call out to a mailer stub would ignore the parameter. - DokuWiki's mail_send() parameter also accepts a "parameters" parameter of parameters for the specific mailer. DokuWiki does not currently use this parameter, but should it ever use it, that would break DokuWiki's mailer-independence. I plan to ignore this parameter too. Suggestions/advice is welcome! ~joe -- DokuWiki mailing list - more info at http://wiki.splitbrain.org/wiki:mailinglist