Squeeze stable upgrade: "RANDR" missing on display

[Erin Brinkley <erinbrinkley@ymail.com>]

I am really stuck today everybody! Another problem with my lenny to squeeze upgrade is that I am constantly getting this error: 

Xlib:  extension "RANDR" missing on display ":0.0".

This happens every time I run a program that opens a new window. Sometimes it makes the program abort. I have my widescreen monitor in portrait mode (rotated), so the display actually WORKS, but I no longer have the xrandr program! So I can't go between landscape and portrait anymore:

$ xrandr 
Xlib:  extension "RANDR" missing on display ":0.0".
RandR extension missing
$

What in the world is going on??? I've done some research and it is a problem that has occured when people use Xinerama with dual head setups ... however, I am NOT using Xinerama and do NOT have a dual head system. I'm running a single head system with the NVIDIA driver. All worked fine yesterday, then I upgraded to squeeze, got the new NVIDIA driver running, and now this error happens constantly. Is this a bug or do I have to reconfigure something?

I'm pasting some stats here...

$ X -version

X.Org X Server 1.7.7
Release Date: 2010-05-04
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.32-5-amd64 x86_64 Debian
Current Operating System: Linux hotstuff 2.6.32-5-amd64 #1 SMP Wed Jan 12 03:40:32 UTC 2011 x86_64
Kernel command line: BOOT_IMAGE=/boot/vmlinuz-2.6.32-5-amd64 root=UUID=83e12130-b601-420c-8509-03faa8358c74 ro noapic nolapic quiet
Build Date: 12 January 2011  02:59:50AM
xorg-server 2:1.7.7-11 (Cyril Brulebois <kibi@debian.org>) 
Current version of pixman: 0.16.4
	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.

$ lspci | grep VGA
00:05.0 VGA compatible controller: nVidia Corporation C51PV [GeForce 6150] (rev a2)

$ grep Driver /etc/X11/xorg.conf
    Driver         "kbd"
    Driver         "mouse"
    Driver         "nvidia"
$