diskpart error: the specified disks have less then 1 mb of free space available.

I have a Dell PowerVault attached to a windows 2008 server. The disk is formatted as a Dynamic NTFS GPT. The page file is not on this volume.

I have added a new disk to the array on the PowerVault and can see it as unallocated space in disk manager contiguous to the existing data volume, when I try to extend the volume using diskpart to add this space I get the following error:

The specified disks have less then 1 mb of free space available

Please specify a disk with at least 1 mb available free space

Any suggestions are appreciated.