accumulation buffer support

[Svilen]

Hi,

I was wondering whether your driver supports accumulation buffers and if 
yes how to enable them.

Here is my platform:
X1600 Mobility Radeon
Linux, Fedora 9
Xorg 7.4 (unofficial)
Mesa 7.1 (unofficial)

xorg.conf
...
    Section "Device"
        Identifier "Videocard0"
        Driver "radeon"
    EndSection
...

A try to get a glx visual with accumulation buffers fails. On Fedora 8 
with ATI driver it works.
Below is the parameter list for glXChooseVisual
GLX_RGBA                                     ,
GLX_RED_SIZE                              , 8,
GLX_GREEN_SIZE                        , 8,
GLX_BLUE_SIZE                           , 8,
GLX_ACCUM_RED_SIZE             , 8,
GLX_ACCUM_GREEN_SIZE       , 8,
GLX_ACCUM_BLUE_SIZE          , 8,
GLX_DOUBLEBUFFER               ,
GLX_NONE

I'll really appreciate your help

Regards
Svilen