The JMS 1.1 specification contains in chapter 11 a detailed list of changes that were introduced in version 1.0.1, 1.0.2, 1.0.2b and 1.1. These all relate to changes made a decade ago. They are of interest only to historians of JMS, and have no value in the JMS 2.0 specification other than to clutter up the spec. They should be removed.
This information will remain in the JMS 1.1 specification for the benefit of future historians.
(For the avoidance of doubt, the JMS 2.0 spec should of course contain a list of changes made between 1.1 and 2.0)