mbrscan is available for esx4.x as part of the Virtual Storage Console. You can run fdisk on the vmdk or log into the VM and verify. For Linux, of the vmdk directly, use fdisk, go into extended mode "x" then "p" to view the partition table. if the first sector starts at 63 instead of 64, then it needs to be aligned. for windows, use msinfo32. Expand Components/Storage/Disks, and look at "Partition Starting Offset". If the offset is 32,256 instead of 32,768, then it needs to be aligned.. Windows 7, and server 2008 are already aligned..
There were issues with it in 5.2 so they might have removed it. I'm pretty sure you can download it from netapp separately though. I believe you can get it also from the VSC 2.0 if you have that loaded though not sure if the version included in that had the bug or not.