Reclaim zeroed space via Vsphere or Vcenter GUI

Hello All,

While i was upgrading our 3 ESXI servers to 5.5 from 5.0 I was playing around in either the windows native vSphere Client or in the vCenter web Client and i stumbled upon an entry offering to reclaim the zeroed space on a Virtual machines VMDK. It said something like "Reclaim Zeroed space on Thick Provisioned disk" or similar.

I am 100% sure it was in the GUI. Does anyone have any clues ?, I am thinking this is probably a new 5.5.1 feature as all previous documentation only mentions CLI options.

Cheers,

benjamin