Message in a PCI bottle - preserving message queue integrity

First, a confession. When David and I started writing this series, we envisioned it would be completed after the third part. It appears we were a bit short-sighted. An astute reader challenged us to help address the concepts of preserving queue message data integrity. With that, we welcome you to part 4.
In parts 1, 2 and 3 of this series we wrote at length about the possible compliance and security issues associated with the queueing of cardholder data (CHD) within a PCI compliant cardholder d