Xen users - Oct 2012 - Xlib: extension "RANDR" missing on display ":1".

I get the message below whenever I run virt-manager via a vnc session.

Xlib:  extension "RANDR" missing on display ":1".

This error disappears when I take off "-extension RANDR" from the
vncserver configuration.  Taking this off makes the VNC session too
big for my monitor.

help.

j