some parse_rfc822_date comments and handling of Y 1970
some parse_rfc822_date comments and handling of Y 1970

git-svn-id: e9fe9b84e32fc5e57b7d09c40cd78b14ea28ed71@572169 13f79535-47bb-0310-9956-ffa450edef68

apache/spamassassin,apache/spamassassin,apache/spamassassin,apache/spamassassin,apache/spamassassin