Disable the mediacheck in a kickstart install

I have been doing several kickstart installs for testing via ftp and each and every time, the kickstart program insists on doing a mediacheck even though the mediacheck option is supposed to be optional in the ks.cfg file: if the option is present, then mediacheck would be accomplished, but if not, it is not supposed to do it.
It is not so bad doing a ftp install, but if you were doing a cdrom install, it would take a long time.
Is there any way to turn this off?