[CentOS] (no subject)

Hi all,
        I've got a bit of an issue with reinstalling a server. I can
get the installer to boot off a memory stick
made with unetbootin, but I can't seem to find the installation files
on the stick. I have hda, sda and sdb
but none are acceptable install media.

How do I mount the USB stick while in the installer to install off it?
DVD isn't an option because it's been
removed for a tape drive.

It's probably something simple I'm missing.

Thanks