Intermittent "AuthenticationException:Command failed to be authenticated!" Errors when using 2 JON agents

Issue

• We've installed two rhq-agents on the same machine, (each one connecting to his respective server, servers are on separated machines) and every few hours it loses connectivity with the JON Server.

• We've checked the logs and see this error:

  2010-08-18 09:06:06,048 ERROR [ClientCommandSenderTask Timer Thread #539] (enterprise.communications.command.client.JBossRemotingRem
  oteCommunicator)- {JBossRemotingRemoteCommunicator.init-callback-failed}The initialize callback has failed. It will be tried again. 
  Cause: org.rhq.enterprise.communications.command.server.AuthenticationException:Command failed to be authenticated!  This command wi
  ll be ignored and not processed: Command: type=[remotepojo]; cmd-in-response=[false]; config=[{rhq.agent-name=awebsar2.audiovisual.e<br />s, rhq.security-token=1vcb5sd0y+/oMRINMn9W7yw8jhBfv2/xW3Naqg6yUH3AUV5THTttgYaIhnDGVAzefyg=, rhq.externalizable-strategy=AGENT}]; par
  ams=[{targetInterfaceName=org.rhq.core.clientapi.server.core.CoreServerService, invocation=NameBasedInvocation[connectAgent]}].