File sytem attributes possibly being reported incorrect

Hi,
I am running GetVolumeInformation to know the attributes of my filesystem.
The filesystem is NTFS and I was able to encrypt certain files in it.
However when I check the flag FILE_SUPPORTS_ENCRYPTION against the one
returned by GetVolumeInformation, it is coming out to be false. Am I missing
something. I am trying in Windows XP.
Regards,
Arati