Using existing lvm2 volumes with clvm?

Hi there,
I have an existing setup of volume groups which I'd like to share on a cluster using iscsi and clvm.

Is this possible?

The volume groups and logical volumes have already been created and the physical volumes are Linux software RAID arrays. The LV's are populated with filesystems which I'd like to make available across the network (for XEN virtualisation and migration).

If I export these physical volumes with iscsi and use them as physical volumes in clvm on other machines, can this be expected to work or will it exterminate the existing volume groups on those physical volumes? :)

Thanks!