This is either https://issues.apache.org/jira/browse/CASSANDRA-4687 or https://issues.apache.org/jira/browse/CASSANDRA-5202
You can run the command “nodetool invalidatekeycache” on all of the server showing the error. If it keeps coming back you may want to disable key cache.
If it is 5202 it should only happen after dropping and recreating a column family using the same name.
