When users permissions are updated for a group chat room, they're not being replicated to the other servers in the cluster.
Also, the participant count is not propagating to the other cluster members.
OK - we have a fix for the MUC room affiliation changes ... this will be in the nightly builds starting tomorrow (dated 05-May-13 and later).
However, I was not able to reproduce the issue reported from the participant count. The numbers seemed to stay in sync across the four members of our test cluster.
Added cluster task to update the cached affiliations for other members. Additional testing is requested; presumed fixed.