Storage vMotion of sims

[FULLSTEAM]

I have two 8.1 sims powered off and sitting on an NFS datastore that I want to decom.  (want the sims, but on a different vol).

Trying to storage vMotion them to the new datastore, I get, from Hard Disk 1:  "The datastore is not compatible with the virtual machine."

Hundreds of other VMs moved without complaint, and regular vMotion works.  Is this some limit built into the sims?

[FULLSTEAM]

OK, this was fun, and I realize that I left out the critical piece for diagnosis.

DSx = datastore number x, DSCx = datastore cluster number X, DC = datacenter, SVMO = Storage vMotion

All tests done by disabling storage DRS during the SVMO.

sim sitting on DS1 sitting in DSC1, SVMO to a DS2 sitting in DSC2, fail.

sim sitting on DS2 sitting in DSC2, SVMO to a DS3 (NOT sitting in a DSC), succeed

DS1 sitting in DSC1, pull DS1 out to where it's just DS1 under a DC, trivial

sim sitting on DS3 (NOT sitting in a DSC), SVMO to DS2 sitting in DSC2, succeed.

DS1 pulled to where it's a DS under the target DSC2, trivial.

sim sitting on DS1 sitting in DSC2, SVMO to a DS2 sitting in the same DSC2, fail

Sims can't handle datastore clusters.  BURT.