The virtualization manager depends on GTK/Gnome's VNC widget to start and work properly. If net-libs/gtk-vnc is not installed, the following error message will be issued by virt-manager at start up (it will quit thereafter): Traceback (most recent call last): File "/usr/share/virt-manager/virt-manager.py", line 467, in <module> main() File "/usr/share/virt-manager/virt-manager.py", line 419, in main from virtManager.engine import vmmEngine File "/usr/share/virt-manager/virtManager/engine.py", line 42, in <module> from virtManager.details import vmmDetails File "/usr/share/virt-manager/virtManager/details.py", line 33, in <module> from virtManager.console import vmmConsolePages File "/usr/share/virt-manager/virtManager/console.py", line 28, in <module> import gtkvnc ImportError: No module named gtkvnc Manually installing net-libs/gtk-vnc-0.4.2-r2 solved the problem, i.e. virt-manager started properly. I recommend to add net-libs/gtk-vnc as a dependency for app-emulation/virt-manager
Its always been a DFEPEND and RDEPEND since the package was added to the tree. Check your setup and make sure you're not using your own overlay or something crazy.