I would like to point you to bom file where all dependencies versions are held:
Other option is to checkout the libraries in the richfaces-showcase example (see the release version 4.2.2.Final, tomcat6 war):
The current version of guava dependency is 11.0.2, the 13.x is not tested yet. I know that upgrading this library caused some problems in the past, so it can be tricky. Please, let us know if come accross and resolve some issues contected with this upgrade.
Thanks Juraj. I tested with 11.0.2 and all worked fine until now!