Cool bug in grub in Centos 6.2 (and therefore in RHEL 6.2)

So if you are like us, you are a belt and suspenders person … you like multiple administrative modalities. You like them because you know they are needed. Because breakage usually happens at the least opportune time, and you need a way in to express your control.
So we have KVM. And we have IPMI. And we have a serial over lan (replacing the old serial consoles).
If you are more that 5 miles away from the gear, you will appreciate having these multiple modes. Including control over power. Yeah, life can be good.
So there you are, adding the functionality to grub.conf to have a serial port made active. So you can grab control that way if needed.
You’ve had to in the past, you know you need it.
Only you make a slight error in the port specification. SOL is on a different TTY than you wrote. No matter, grub has done the right thing in the past, you can rely upon it to not completely muck your day up… right?
Well, if you do mess with grub, have super rescue CD around, on a bootable USB stick (we have it via PXE as well).
Because that one ever so slightly off parameter will freeze grub at the 1.5 stage with a loading message that never goes away.
Ain’t that fun?
Minor typos can be fatal. Cool bug. For various lethal definitions of “Cool”
[stares numbly at the screen realizing that he cant get these hours he wasted, back in his life]