I've been working on getting a PXE server going, sort of going by this article (http://www.debian-administration.org/articles/478 ). I am copying the files from the iso files into /tftpboot/ and creating menus to boot it up. My trouble is coming part way through the boot process on Ubuntu and Kubuntu (so far, no problems with Backtrack or CrunchBang), it comes up trying to load from a CD.
Part way through booting on the screen it says
Begin trying nfs mount -o nolock -o ro /cdrom
Then continues for a few seconds and then stops at
Using CD-ROM mount point /cdrom/
Identifying.. [random set of alphanumeric characters changing every time]
Is there a way to prevent it looking for a /cdrom/ device? Here is one of my menus I have set up:

        MENU LABEL Ubuntu 10.04LTS 32bit, Desktop (Gnome interface)
                KERNEL /Ubuntu/10.04LTS/32bit/Gnome/casper/vmlinuz
                APPEND initrd=/Ubuntu/10.04LTS/32bit/Gnome/casper/initrd.lz boot=casper text rootfstype=nfs root=/dev/nfs netboot=nfs nfsroot= 
        TEXT HELP
                Boot Ubuntu 10.04LTS 32bit, Desktop (Gnome interface)