migration import using hsm policy

Hi am trying to import a backup created with the migration tool. There is am option to apply the hsm policy when importing the backup, but the checkbox is grayed out and it says this below the check box:

hsm policy not available, please check the zextras powerstore settings

I have created a policy and restarted the server, but it still does not allow me to check the box. I am using zimbra 7.2.1 NE on ubuntu 10.04.

Any advice?