Fencing fail on Red Hat Cluster Suite when using HP's iLO3 ?

Issue

• Sometimes we get following errors on the cluster nodes when a fence is initiated and the host fails to get fenced:

fence_localhost1_iLo3_monitor_60000 on itmu-localhost-cl1 'unknown error' (1): call=135, status=Error, last-rc-change='Mon 13:40:13 2014', queued=1175ms, exec=0ms

Error: Received an Unexpected RAKP 2 message
packet session id 0x0 does not match active session 0xa0a2a3a4
ipmitool: lanplus.c:1167: read_session_data_v2x: Assertion `0' failed.

• The fence device have been configured properly on the cluster nodes.
• What is causing such problem to appear?