When trying use Ubuntu Feisty with and Intel 945GM/GMS/940GML display adapter to implement Beryl/Compiz/Compiz Fusion running glxinfo returns:

# glxinfo | grep direct
direct rendering: No

The following sections are present in xorg.conf (note: not complete sections):

Section "Module"
Load    "bitmap"
Load    "dbe"
Load    "ddc"
Load    "dri"
Load    "extmod"
Load    "freetype"
Load    "glx"
Load    "int10"
Load    "vbe"
EndSection

Section "Device"
Identifier "Intel Corporation Mobile Integrated Graphics Controller"
Driver "i810"
BusID "PCI:0:2:0"
Option "XAANoOffscreenPixmaps" 
EndSection

Section "DRI"
Mode 0666
EndSection

Section "Extensions"
Option "Composite" "Enable"
EndSection

Run the following command before running compiz or beryl:

export LD_PRELOAD=/usr/lib/fglrx/libGL.so.1.2.xlibmesa