QPID-5985: change request for 0.30

Justin,

I made a change on trunk before the 0.30 branch for QPID-5985[1] to fix
a regression that had crept in several release back. Unfortunately in my
haste I caused another regression.

This second issue has now been fixed on trunk[2] and I'd like to merge
it on to 0.30. Alan has reviewed and approved the change for 0.30.

--Gordon

[1] https://issues.apache.org/jira/browse/QPID-5985
[2] https://svn.apache.org/r1617924