ORA-32701 Possible hangs up to hang ID=0 detected

Bug 10013431  Hang / ORA-32701 during / after startup in RAC

 This note gives a brief overview of bug 10013431 (Doc ID 10013431.8 )

This problem is introduced in 11.2.0.2 .

Shortly after or during instance startup in RAC, one or many of the instances
end up in a hang state waiting for a LB or NB DLM resource.

Rediscovery Notes:
 - RAC on 11.2.0.2 
 - a hang occurs shortly after instance startup where there is no blocking
   session to be found from system state or hang analysis
 - Alert messages like below may be seen;
 "ORA-32701: Possible hangs up to hang ID=0 detected"

This bug is fixed in 11.2.0.2.1 ( 11GR2 patchset 1, PSU1 )