7.0 toolkit not recognized by xencenter on ubuntu vms from 6.5 guests

We have a bunch of Ubuntu VM's running and are created on xenserver 6.5 SP1, they all had the 6.5 toolkit installed before we upgraded xenserver to 7.0

Once we upgraded xenserver we also upgraded the toolkit on each vm.

However, XenCenter still sais "Management Agent not installed" but I can see on the VM's that the 7.0 package has been installed and that the xe-daemon is running.