Pass back cookies properly through reverse proxy

PR: 6055
Obtained from: "Eidelman, Brian" <BEidelman@netegrity.com>
Submitted by:	"Eidelman, Brian" <BEidelman@netegrity.com>
Reviewed by:	Chuck Murcko


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@91129 13f79535-47bb-0310-9956-ffa450edef68