Link: http://trac.tools.ietf.org/wg/httpbis/trac/ticket/44
Origin: http://www.w3.org/mid/45478C36.8080907@gmx.de
Component: p7-auth
RFC1866 and RFC2069 aren't mentioned anywhere in the spec. These references probably are leftovers from revising RFC2068.
Removed earlier.