[libvirt-users] virt-viewer and virt-manager problem

Hello, here is my problem : i migrated an old debian server, with kvm host and guests vm, on a new one (wheezy to jessie). Everything worked fine on this old server. On the new server, i created a storage pool, copy the qcow2 guests files (from the old server) inside this storage pool, copy the xml guests files (from the old server) to /etc/libvirt/qemu , then virsh define guests and virsh start guests. Every guests works fine. My problem is about virt-viewer and virt-manager when i connect from my station to my kvm host from ssh (ssh -X 192.168.151.248). I cant use virt-manager or virt-user virt-manager display all the guests but i cant display the guest itself or the guest informations virt-viewer open a blanck window when i do vncviewer 192.168.151.248:5906 it works fine then i think the problem come from virt-viewer and virt-manager, but i cant see where is the problem. Does someone could help to solve this problem. Thanks -- Pascal