Thanks
I misread the KB but its strange that this option is enabled in the vSphere 5.1 GA environment that I have but I see that the Availability Guide also clearly states that this option is disabled for ESXi hosts in HA cluster. Either I am lucky 
or I probably need to check again after few hours.
-Arun
Twitter: https://twitter.com/arunpande
Blog: http://highoncloud.blogspot.in/
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