Python email.MIMEText.MIMEText.as_string incorrectly folds long subject header

Solution Verified - Updated -


Long subject headers are folded using a newline and tab in email.MIMEText.MIMEText.as_string. While this is not exactly prohibited by RFC 822 it breaks mail clients like Thunderbird and Outlook.


  • Red Hat Enterprise Linux 6.1
  • Python 2.6

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