Wednesday, October 21, 2009

Two SMTP Service Bug Fixes

Tonight we've deployed two bug fixes to the SMTP relay service:
  1. Previously, emails sent with very long Subject lines, such that the Subject line folded onto the next line, were improperly processed, and this could result in headers being visible in the email body. This is now fixed.
  2. Previously, emails sent with very long From lines, such that the From line folded onto the next line, were improperly processed, and this could result in the email not being transmitted to the final recipient at all. This is now fixed.
  3. Previously, encoded subject lines, such as:

    =?utf-8?Q?You've_received_=E2=82=A8229.64_($2.00_USD)_in_your_Surveyhead_?= =?utf-8?Q?account?=

    would not have their encoding preserved. This is also now fixed.
Technical Resources:

Those wishing to read about the allowance of folded lines as stated in the SMTP specification can do so here: http://www.faqs.org/rfcs/rfc822.html. Specifically, read section:

3.1.1. LONG HEADER FIELDS