SpamAssassin Rule: STOX_REPLY_TYPE
Standard description: none
The mail's content type is "text/plain" and has the "reply-type=original" attribute.
The default scores for this rule can be found in the online list of tests.
There is no IANA registration for the MIME "text/plain" Media Type sub-parameter "reply-type" at this time. This is a non-standard and undefined parameter.
However this parameter does appear to be used in Microsoft software such as Outlook Express (ref).