nvidia quadro nvs 135m does not 1600x1200 / linux

[delluser]

Hi there

I just bought a Dell Latitude D630 equipped with a Quadro NVS 135M *[1].
It works well *[2] with Kernel 2.6.25.6 and the current 173.14.05 driver (Debian testing/lenny). However when I attach a 1600x1200 Monitor to the port replicator
(dvi), the monitor is correctly recognized, but the nvidia driver does not allow
any resolution beyond 1440x900 *[3].
(The official open source nv driver does, but is far to slow for work)

Is there any way to allow 1600x1200 with the current nvidia driver?
Should I try one of the legacy drivers instead?
Is there hope that future versions will support this scenario?

Kind Regards,
Holger

Appendix:

*[1] output from "lspci -v":

01:00.0 VGA compatible controller: nVidia Corporation Quadro NVS 135M (rev a1)
Subsystem: Dell Device 01f9
Flags: bus master, fast devsel, latency 0, IRQ 16
Memory at fd000000 (32-bit, non-prefetchable) [size=16M]
Memory at e0000000 (64-bit, prefetchable) [size=256M]
Memory at fa000000 (64-bit, non-prefetchable) [size=32M]
I/O ports at df00 [size=128]
[virtual] Expansion ROM at fc000000 [disabled] [size=128K]
Capabilities: [60] Power Management version 2
Capabilities: [68] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
Capabilities: [78] Express Endpoint, MSI 00
Capabilities: [100] Virtual Channel <?>
Capabilities: [128] Power Budgeting <?>
Capabilities: [600] Vendor Specific Information <?>
Kernel driver in use: nvidia
Kernel modules: nvidiafb, nvidia

*[2] I only got some minor glitches (black horizontal stripes in the background) when running glxgears.

*[3] from Xorg.0.log
...
(II) NVIDIA(0): NVIDIA GPU Quadro NVS 135M (G86GL) at PCI:1:0:0 (GPU-0)
(--) NVIDIA(0): Memory: 262144 kBytes
(--) NVIDIA(0): VideoBIOS: 60.86.47.00.09
(II) NVIDIA(0): Detected PCI Express Link width: 16X
(--) NVIDIA(0): Interlaced video modes are supported on this GPU
(--) NVIDIA(0): Connected display device(s) on Quadro NVS 135M at PCI:1:0:0:
(--) NVIDIA(0): CMO (DFP-0)
(--) NVIDIA(0): FUS P20-2 (DFP-1)
(--) NVIDIA(0): CMO (DFP-0): 330.0 MHz maximum pixel clock
(--) NVIDIA(0): CMO (DFP-0): Internal Dual Link LVDS
(--) NVIDIA(0): FUS P20-2 (DFP-1): 165.0 MHz maximum pixel clock
(--) NVIDIA(0): FUS P20-2 (DFP-1): Internal Single Link TMDS
(II) NVIDIA(0): Assigned Display Device: DFP-0
(WW) NVIDIA(0): No valid modes for "1600x1200"; removing.
(II) NVIDIA(0): Validated modes:
(II) NVIDIA(0): "1440x900"
(II) NVIDIA(0): "1024x768"
(II) NVIDIA(0): "800x600"
...