occult nvidia kernel version skew

[hendrik@topoi.pooq.com]

I'm having trouble getting my nvidia card working on kernel
vmlinuz-2.6.15-1-amd64-generic.  It works fine with vmlinuz-2.6.12-1-amd64-generic.

Both kernels are stock Debian kernels, installed from Debian etch 
mirrors, or from Len Sorenson's installation CD.  2.6.15-1 was 
definitely from the Debian mirrors.

According to aptitude, used interactively, I have installed the 
following modules contining the word 'nvidia':
  nvidia-glx 1.0.8762-2
  nvidia-glx-dev 1.0.8762-2
  nvidia-kernel-2.6.12-1-amd64-generic 1.0.8762-2
  nvidia-kernel-source 1.0.8762
  nvidia-kernel-common 20051028+1
  nvidia-xconfig 1.0+200511
  nvidia-kernel-2.6.15-1-amd64-generic 1.0.8762-2

And the virtual packages  nvidia-kernel-1.0.8756 and 
nvidia-kernel-1.0.8762 are both highlighted.  (what does this mean?  Is 
it a clue?)

(note: interactive aptitude may have truncated some version numbers to 
10 characters.  I wish it didn't, or at least, that when I make the 
screen wider, it would stop truncating rather than give me more white 
space.  But that's another problem)

The problem I am havind appears to be version skew.  When booting,
X fails to start, leavain the following in /var/log/messages

Jun 14 08:33:38 april kernel: NVRM: API mismatch: the client has the version 1.0-8762, but
Jun 14 08:33:38 april kernel: NVRM: this kernel module has the version 1.0-8756.  Please
Jun 14 08:33:38 april kernel: NVRM: make sure that this kernel module and all NVIDIA driver
Jun 14 08:33:38 april kernel: NVRM: components have the same version.

leading to the following in /var/log/Xorg.0.log:

(II) Setting vga for screen 0.
(**) NVIDIA(0): Depth 24, (--) framebuffer bpp 32
(==) NVIDIA(0): RGB weight 888
(==) NVIDIA(0): Default visual is TrueColor
(==) NVIDIA(0): Using gamma correction (1.0, 1.0, 1.0)
(**) NVIDIA(0): Enabling RENDER acceleration
(EE) NVIDIA(0): Failed to initialize the NVIDIA kernel module! Please ensure
(EE) NVIDIA(0):     that there is a supported NVIDIA GPU in this system, and
(EE) NVIDIA(0):     that the NVIDIA device files have been created properly. 
(EE) NVIDIA(0):     Please consult the NVIDIA README for details.
(EE) NVIDIA(0):  *** Aborting ***
(II) UnloadModule: "nvidia"
(II) UnloadModule: "ramdac"
(II) UnloadModule: "fb"
(EE) Screen(s) found, but none have a usable configuration.

Fatal server error:
no screens found

As far as I know, I have *nothing* left from version 8756.
Except for that one virtual package, which is bold-faced
for no obvious reason, but whose dependencies are all marked purged.

Where do I start to look for the 8756 stuff that it finds but I can't?
Or is this a spurious error message and is something else to blame?

-- hendrik