rmail-retry-ignored-headers

rmail-retry-ignored-headers is a variable defined in `rmail.el'.
Its value is

"^x-authentication-warning:\\|^x-detected-operating-system:\\|^x-spam[-a-z]*:\\|content-type:\\|content-transfer-encoding:\\|mime-version:\\|message-id:"

Documentation:
Headers that should be stripped when retrying a failed message.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 23.2 of Emacs.