Registry trouble in a cluster

I'm getting the following exception all over the logs in a clustered environment :

org.apache.hivemind.ApplicationRuntimeException: The ServiceSerializationSupport instance has not been set; this indicates that the HiveMind Registry has not been created within this JVM.

The application seems to work ok, but we are also having some session replication problems with the same application that might be related to this issue also.
Any ideas about might be causing this would be great. I'm using hivemind-1.1.1.