i tried with qemu 0.9.1-10lenny1 and it actually seemed to network boot fine with pxelinux (except for the default network card, ne2k_pci).
since that version doesn't support kvm, i tried qemu 0.12.x with kvm support disabled, and that seemed to also work. so specifically, it appears to be a problem with the interaction of newer versions (4.x) of syslinux/pxelinux and qemu with kvm support enabled. wheee. live well, vagrant -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org