Comment 1 for bug 203020

I was not able to attach a CDROM device either.

via virsh, I get this:
attach-disk winxp /home/martin/path/to/my.iso hdc --mode readonly --driver file --type cdrom
(I tried various combinations of --driver, --type and --mode as well as hda,hdc,/dev/hdc,cdrom,/dev/cdrom and /dev/media for the target)

via virt-manager, I get this in an error box after completing the "add storage" wizard:
Unable to complete install: 'Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/addhardware.py", line 514, in add_device
    self.vm.add_device(xml)
  File "/usr/share/virt-manager/virtManager/domain.py", line 729, in add_device
    raise RuntimeError, "Unable to attach device to live guest, libvirt reported error:\n" + device_exception
RuntimeError: Unable to attach device to live guest, libvirt reported error:
virDomainAttachDevice() failed CDROM not attached, cannot change media'