Hmmm there's another 2.1.8 problem reported here:
When you say "or newer" does this mean you have tested it on 2.1.9 and it also doesn't work? If there is an
incompatibility with 2.1.8/9 the best thing would be to log an issue in the issue tracker
https://issues.jboss.org/browse/RF along with some code that reproduces the problem.
I just upgraded to 2.1.9 and my app seems ok with RF 4.2.1.Final, maybe it's a specific problem with
rich:tree (& a4j:repeat).
Could you please provide minimal code example which produces the error?