Hey Craig,
Which protocols are you guys using? Any NFS?
Looking at the IMT, it seems FC and iSCSI are supported for 5.1, but no NFS.
I'm sure this will change very soon, the new VSC is in a public beta, and i'm sure new support will be added with its release.
I would also try and get your Data ONTAP upgraded to at least 8.0.3 which is the latest stable release of 8.0.x, and 8.1.1 being the latest stable 8.1.x release.