Unable to boot guest domain

In Opensuse 11.1 from the gui I selected the cdrom drive and selected the path for the iso image. When I click on OK I get the following message:

The installation source is containing an unsupported format.

Please let me know how to resolve this?

are you trying to boot 11.1 in a VM?
have you loop mounted the iso?
have you md5sum checked the iso?
is the iso architecture (32, 64, PPC, what?) compatible with your