rfc5451.txt:Murray S. Kucherawy:sendmail:usa:41:apr:2009:UNKNOWN:abnf,kwd,seccons,ianacons:draft-kucherawy-sender-auth-header:2009-01-27:2008-09-29:37:0:40:46:123:4:2004-09-10:0::2004-09-10:1479:2009-04-20:83