Vista guest and touchpad tapping problem

Hi,

When playing a bit with KVM I encountered a small inconvenience with touchpad. When I pass the “-usbdevice tablet” parameter to kvm it does mouse pointer to work correctly under VNC, i.e. coords are adequate to real mouse pointer but I’m unable to simulate left mouse button press by tapping the pad. Is there any solution to this issue ?

Thanks in advance
Cheers