CentOS virt - Jan 2011 - How to send sysrq on "virsh console"

I have a KVM guest running on CentOS 5.5 that is in a bad state.   I
would like to dump the kernel information using magic-sysrq commands,
but I cannot figure out how to send a break on the virtaul serial port
provided by "virsh console".

The guest is a standard install that will respond if I can send a
break on the virtual serial port.

Is it possible to send a break on the virtual serial port?

Thanks,
   David