We presume , that xen-3.4.1-5.fc12.src.rpm has been already installed on the system and Xen Host been built via mentioned “rpm” , Libvirt 0.7.1-15 and 2.6.31.6 pvops kernel is up and running at the time of upgrade. Apply following patch to /root/rpmbuild/SPECS/xen.spec

Regardless bug with failure checksum offloading was fixed in SNV_81 , i.e. a while ago. OpenSolaris 2009.06 PV DomU install at Xen 3.4.1 Linux Dom0 appears still to be affected. Wrong checksum may be easily captured via tcpdump on the LAN due to DHCPDISCOVER request issued by OSOL installer is a broadcast request.