There is a mailing-list libvir-list@redhat.com for libvirt, with an on-line archive. Please subscribe to this list before posting by visiting the associated Web page and follow the instructions. Patches with explanations and provided as attachments are really appreciated and will be discussed on the mailing list. If possible generate the patches by using cvs diff -u in a CVS checkout.
We expect to use Red Hat Bugzilla to track bugs for libvirt, though there isn't a libvirt software module defined yet, in the meantime use the mailing-list, thanks !.