+ * autobuild - A flag to indicate if the composition file parser is
+ * being run in automatic mode or not. In auto mode,
+ * if a MIME-Version header is encountered it is assumed
+ * that the composition file is already in MIME format
+ * and will not be processed further. Otherwise, an
+ * error is generated.
+ * dist - A flag to indicate if we are being run by "dist". In
+ * that case, add no MIME headers to the message. Existing
+ * headers will still be encoded by RFC 2047.