Copy and Paste

I have tried multiple combinatios:
RHEL 5 VM with RHEL 5 client
RHEL 5 VM with RHEL 6 client
RHEL 6 VM with RHEL 6 client
RHEL 6 VM with RHEL 6 client
RHEL 6 VM with WindowsXP client

I have spice-vdagent and rhev-agent running in the VMs (rhel 5 from epel), and no matter what I do, I cannot copy text from the VM and paste it to a window on the client, and vice versa. Is there some sort of secret switch that is needed?

Thanks,

Kenny