XFree86 4.1: S3 virge driver on linux 2.4.xx at alpha machine: kernel bug?

Hi,

Since a year, I used a Elsa Gloria L/MX with the linux 2.4.19 kernel
without any trouble. After switching to srm console (alpha specific),
the graphics adapter was not longer recognized and I changed the Gloria
to an old S3 virge card. I reconfigured X and startet X with startx.

Now, after startx was invoked, the screen becomes black at first, and 
after some seconds the screen displays funny color pixels, and ... 
nothing else. The kernel hangs. I have to reset the board. I tried the 
2.2.xx linux kernel with success.

Has anyone an idea, was the reason for this is and how to fix it? -- One
time, I got a softreset and the board was rebooted after I started X
with the S3 virge driver. In this case I got ECC-error msgs from the
kernel. I suppose that the driver sets some registers. But not the
registers of the graphics adapter! And this causes the kernel hang.

Best regards

     Harald