[libvirt-users] Dump network traffic from each VM.

Hi guys, Does anybody know how to dump the network trafic from each virtual machine using libvirt? Here, we usually use VPN softwares and other network tools inside Virtual Machines (Windows and Linux). Sometimes, this applications does not work properly, so we need to dump the network traffic of each Virtual Machine to compare and debug. How can I enable it using libvirt? I know that if you use a QEMU instance, you can enable the dump using "-netdev dump,...". Thanks! :-) Julio Cesar Faracco