SAS Drive Firmware update is not compatible PE2950 WHS2011

I'm running a retired PE2950 and MD1000 at home with MS Windows Home Server 2011 which is basically  Server 2008 R2 under the skin.

I have 4 x ST373455SS 73G 15k drives.

I'm trying to update the SAS Drive Firmware from S512 to the current S52C

I have down loaded the file SAS-Drive_Firmware_NYHRG_WN32_S52C_A01, and run it as described, and it starts and inventory, however I then get an error:

"This Update Package is not compatible with your system configuration"

Am I missing something, or is the package objecting to WHS2011.

If the latter is there a work around?

Thanks for any help

Peter