host is compatible with versions (<UNKNOWN>) and cannot join cluster

Hello,

Fresh install of RHEV and using version 3.1. I have RHEV-M up and running, however, when I attempt to add our hypervisors (HP BL460c Gen8) I recieve the following error message "Host [servername] is compatible with versions () and cannot join Cluster POC-DEV-TEST which is set to version 3.1"

The hypervisors and management server are running a base install of RHEL 6.3. I am not using the rhev-h ISO to built the hypervisors. I'm pushing the hypervisor packages over from the management box. Everything seems to go well, but when the hypervisors come back up I receive the error message posted above. 

I opened a ticket early this morning, but have not heard back yet. Any ideas for troubleshooting in the mean time?

Thanks in advance,

Brian