Merged QPID-6052 (r1621143 r1621148 r1621149 r1621150 r1621826) to 0.30 from trunk

git-svn-id: https://svn.apache.org/repos/asf/qpid/branches/0.30@1622044 13f79535-47bb-0310-9956-ffa450edef68