Today I downloaded Cisco's Virtual Wireless Controller to play around with.
I wanted to run the controller in VirtualBox, but simply importing the downloaded .OVA file didn't work straight away. After the import was done, I ended up with a virtual machine configuration, where a bootable image was missing. So I had to untar the .OVA file by myself:
$ tar xvf AIR-CTVM-K9-8-0-110-0.ova
And then set the extracted ISO image as bootable CD:
Last I changed the boot order to first boot from HD and second from CD/DVD:
Now the installation of the Wireless Controller was running as desired.