The next major release of Message Queue may introduce changes that make your clients incompatible with that release. This information is provided now to allow you to prepare for these changes.
The locations of individual files installed as part of Sun Java System Message Queue might change. This could break existing applications that depend on the current location of certain Message Queue files.
3.5 and earlier brokers may no longer be able to operate in a cluster with newer brokers.
In future releases Message Queue clients may not be able to use JDK versions that are earlier than 1.3.