I think the line that uxan is referring to is the one similar to this :
co:2345:respawn:/sbin/agetty ttyS0 9600 vt100-nav
It is used to create a tty login session to ttyS0 which should be the serial console port on your server.
By commenting this out and entering "init q", the error should disappear, however, you will no longer have a login prompt via your LOM (if configured). I understand that a similar entry exists for use with Xen, but the ttyS0 will be different.
I am still looking into this issue and if I resolve then I will update the post.