https://issues.redhat.com/browse/JGRP-2401 added a version field to the configuration. The idea was to abandon start of a channel if the JGroups version and the version used in the config differed too much. However, there are a few drawbacks:

• Config files might have a missing version. In this case, a warning is emitted, but the stack is started correctly
• Incorrect expansion of the version by the release process led to errors (stack not starting)
• Anybody could either remove the version and change it manually to be able to start a stack. This defies the purpose

Therefore, we'll remove version again! Instead, the following things will be done:

• Old and deprecated protocol use will be detected. Example: UNICAST and UNICAST2 will be annotated as deprecated, and warnings will be issued when starting with deprecated protocols. This is essentially the same as for deprecated attributes.