Description of problem: Installing a guest adding the --nographics switch using virt-install causes libvirtError and does not allow a guest to be installed

[root@ibm-dx360m2-02 ~]# virt-install --connect qemu:///system --hvm --name rhel555 --nographics --ram 1024 --vcpus=1 --location http://download.lab.bos.redhat.com/redhat/released/RHEL-5-Server/U5/x86_64/os --disk path=/var/lib/libvirt/images/rhel555.img.raw,size=5,device=disk,bus=virtio --debug --os-variant=virtio26 --accelerate --extra-args "console=tty0 console=ttyS0,115200"
Tue, 07 Dec 2010 17:13:36 DEBUG    Requesting libvirt URI qemu:///system
Tue, 07 Dec 2010 17:13:36 DEBUG    Received libvirt URI 'qemu:///system'
Tue, 07 Dec 2010 17:13:36 DEBUG    Requesting virt method 'hvm'
Tue, 07 Dec 2010 17:13:36 DEBUG    Received virt method 'hvm'
Tue, 07 Dec 2010 17:13:36 DEBUG    Hypervisor name is 'kvm'
Tue, 07 Dec 2010 17:13:36 DEBUG    parse_disk: returning ('/var/lib/libvirt/images/rhel555.img.raw', None, None, 'disk', 'virtio', False, False, 5.0, True, None)
Tue, 07 Dec 2010 17:13:36 DEBUG    Detected storage as type 'file'
Tue, 07 Dec 2010 17:13:36 DEBUG    Setting os type to 'linux' for variant 'virtio26'
Tue, 07 Dec 2010 17:13:36 DEBUG    DistroInstaller location is a network source.


Starting install...
Tue, 07 Dec 2010 17:13:36 DEBUG    Attempting to detect distro:
Tue, 07 Dec 2010 17:13:36 DEBUG    Fetching URI: http://download.lab.bos.redhat.com/redhat/released/RHEL-5-Server/U5/x86_64/os/.treeinfo
Tue, 07 Dec 2010 17:13:36 DEBUG    Saved file to /var/lib/libvirt/boot/virtinst-.treeinfo.EP3NNc
Retrieving file .treeinfo...                             |  442 B     00:00     
Tue, 07 Dec 2010 17:13:36 DEBUG    Fetching URI: http://download.lab.bos.redhat.com/redhat/released/RHEL-5-Server/U5/x86_64/os/images/pxeboot/vmlinuz
Tue, 07 Dec 2010 17:13:36 DEBUG    Saved file to /var/lib/libvirt/boot/virtinst-vmlinuz.tzQXnF
Retrieving file vmlinuz...                               | 1.9 MB     00:00     
Tue, 07 Dec 2010 17:13:36 DEBUG    Fetching URI: http://download.lab.bos.redhat.com/redhat/released/RHEL-5-Server/U5/x86_64/os/images/pxeboot/initrd.img
Tue, 07 Dec 2010 17:13:37 DEBUG    Saved file to /var/lib/libvirt/boot/virtinst-initrd.img.o6mU_e
Retrieving file initrd.img...                            | 7.7 MB     00:00     
Tue, 07 Dec 2010 17:13:37 DEBUG    Creating guest from:
<domain type='kvm'>
  <name>rhel555</name>
  <currentMemory>1048576</currentMemory>
  <memory>1048576</memory>
  <uuid>33bfbbca-d54f-5ea7-9c24-61ea5ba311ec</uuid>
  <os>
    <type arch='x86_64'>hvm</type>
    <kernel>/var/lib/libvirt/boot/virtinst-vmlinuz.tzQXnF</kernel>
    <initrd>/var/lib/libvirt/boot/virtinst-initrd.img.o6mU_e</initrd>
    <cmdline>method=http://download.lab.bos.redhat.com/redhat/released/RHEL-5-Server/U5/x86_64/os console=tty0 console=ttyS0,115200</cmdline>
  </os>
  <features>
    <acpi/><apic/><pae/>
  </features>
  <clock offset="utc"/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>destroy</on_reboot>
  <on_crash>destroy</on_crash>
  <vcpu>1</vcpu>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <console type='pty'/>
    <disk type='file' device='disk'>
      <driver name='qemu' cache='none'/>
      <source file='/var/lib/libvirt/images/rhel555.img.raw'/>
      <target dev='vda' bus='virtio'/>
    </disk>
    <interface type='network'>
      <source network='default'/>
      <mac address='54:52:00:3b:e4:e2'/>
      <model type='virtio'/>
    </interface>
    <input type='mouse' bus='ps2'/>
  </devices>
</domain>

Tue, 07 Dec 2010 17:13:37 DEBUG    Removing /var/lib/libvirt/boot/virtinst-vmlinuz.tzQXnF
Tue, 07 Dec 2010 17:13:37 DEBUG    Removing /var/lib/libvirt/boot/virtinst-initrd.img.o6mU_e
Tue, 07 Dec 2010 17:13:37 ERROR    internal error Process exited while reading console log output: Unknown vga type: none

Domain installation may not have been
 successful.  If it was, you can restart your domain
 by running 'virsh start rhel555'; otherwise, please
 restart your installation.
Tue, 07 Dec 2010 17:13:37 ERROR    internal error Process exited while reading console log output: Unknown vga type: none
Traceback (most recent call last):
  File "/usr/sbin/virt-install", line 892, in ?
    main()
  File "/usr/sbin/virt-install", line 754, in main
    start_time, guest.start_install)
  File "/usr/sbin/virt-install", line 816, in do_install
    dom = install_func(conscb, progresscb, wait=(not wait))
  File "/usr/lib/python2.4/site-packages/virtinst/Guest.py", line 541, in start_install
    return self._do_install(consolecb, meter, removeOld, wait)
  File "/usr/lib/python2.4/site-packages/virtinst/Guest.py", line 633, in _do_install
    self.domain = self.conn.createLinux(install_xml, 0)
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1277, in createLinux
    if ret is None:raise libvirtError('virDomainCreateLinux() failed', conn=self)
libvirtError: internal error Process exited while reading console log output: Unknown vga type: none


Version-Release number of selected component (if applicable):

]# rpm -qa | grep libvirt
libvirt-python-0.8.2-13.el5
libvirt-0.8.2-13.el5

How reproducible:
100% on the systems I tried

Steps to Reproduce:
1. install rhel 5.6 with virtulaization
2. run the virt-install command with the --nographics switch
3.
  
Actual results:
libvirtError

Expected results:
guest should install without error

Additional info:

[root@ibm-dx360m2-02 ~]# virsh uri
qemu:///system

[root@ibm-dx360m2-02 ~]# virsh hostname
ibm-dx360m2-02.rhts.eng.bos.redhat.com

[root@ibm-dx360m2-02 ~]# virsh nodeinfo
CPU model:           x86_64
CPU(s):              16
CPU frequency:       1596 MHz
CPU socket(s):       1
Core(s) per socket:  4
Thread(s) per core:  2
NUMA cell(s):        2
Memory size:         16476120 kB