Step #01

download an alternative bios file, that supports UEFI

> wget -c http://downloads.sourceforge.net/project/edk2/OVMF/OVMF-X64-r11337-alpha.zip
>unzip OVMF-X64-r11337-alpha.zip OVMF.fd

Step #02

create a disk image

> qemu-img create -f raw linux.img 25G

Step #03

boot into UEFI – not secure boot

> qemu-kvm linux.img \
    -bios OVMF.fd 
    -m 1024 \
    -cdrom Fedora-18-x86_64-Live-Desktop.iso \
    -boot d \
    -usbdevice tablet

With virt-install

virt-install -n f18efi -r 1024 -f linux.img -c /mnt/backup/VMs/iso/Fedora-18-x86_64-Live-Desktop.iso --boot loader=/mnt/backup/VMs/images/uefi/OVMF.fd  --graphics vnc