Change SE-Sparse disk size

Hi guys,

Iv'e recently read about Storage-Efficient disk (aka SE-Sparse/FLEX-SE)

Space Efficient Virtual Disks – In Practice | VMware End-User Computing Blog - VMware Blogs

I'm running VSphere 5.1.

I was able to create SE-Sparse disk via vmkfstools (-d sesparse) and via VCenter API.

It is working fast, just great. (IOPS Increased up to 3 times).

However  i could not find a way to increase disk size when its SE-Sparse.

API gives error, in web client the disk size button is grayed out, and vmkfstoold -X give 'invalid disk parameter'. (all work on thin\thick disks)

Anyone have a solution\work around to do so?

Thanks!