Comment 5 for bug 910058

* Do you see this only with windows guests?
No, most of our KVM machines are Debian and/or Ubuntu. I didn't yet tried a Windows guest.

* Is there a linux distribution/release with which you can reproduce this?

Distribution/release which works as expected:

# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 10.04.4 LTS
Release: 10.04
Codename: lucid

virt-manager (0.3.10-2ubuntu2.2)
libgtk-vnc-1.0-0 (0.3.10-2ubuntu2.2)
python-gtk-vnc (0.3.10-2ubuntu2.2)

Distribution which works slow:
# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 12.04.4 LTS
Release: 12.04
Codename: precise

virt-manager (0.9.1-1ubuntu5.1)
libgtk-vnc-1.0-0 (0.5.0-1ubuntu1)
libgtk-vnc-2.0-0 (0.5.0-1ubuntu1)
python-gtk-vnc (0.5.0-1ubuntu1)