virtio network in kvm guest doesn't work

Sorry if i’m in the wrong forum - i didn’t find a better place…

When i start a virtual machine guest (OpenSUSE 11.1) with the following parameters

qemu-kvm -hda /home/kvm/vms/xxx_yyy_SuSE11.1.qcow2 -daemonize -net nic,model=virtio -net tap -k de -m 2048 -smp 4 -vnc :0

i can’t get the virtio network card to work - although other interfaces (e.g. e1000) do. Other linux guests do accept virtio interfaces. Host is also SUSE 11.1.

Yast says: “Unable to configure the network card because the kernel device (eth0, wlan0) is not present. This is mostly caused by missing firmware (for wlan devices). See dmesg output for details.”

Dmesg shows no errors:

ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 11
virtio-pci 0000:00:03.0: PCI INT A -> Link[LNKC] -> GSI 11 (level, high) -> IRQ11

lsmod says:

virtio_net   10584 0
virtio   4568 3 virtio_balloon,virtio_net,virtio_pci

any hints?
thanks,
Kai