Comment 43 for bug 363812

I have a Lenovo x200 running Jaunty 64, with similar issues, and I've looked at a few other bugs that also have strange "disappearing device" behaviour, such as:
https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/287893
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/334413

I've been observing this for about 3 weeks now trying to find a meaningful pattern that would help track this down, but I can't.

My observations:
Sometimes the card appears, sometimes it does not. When it does, it works fine using Network Manager, although I've yet to test the suspend / resume functionality that people have been having issues with.

When it does not:
 - There is no /dev/ttyACM[012].
 - It doesn't show up in lsusb.
 - There is nothing in dmesg hinting towards it (not even messages about cdc_acm).
 - Cycling Fn-F5 only affects Bluetooth and Wifi.
 - /sys/devices/platform/thinkpad_acpi/wwan_enable does not exist.

I'm currently running on 2.6.31-020631rc5-generic but have also tried v2.6.31-rc4, v2.6.31-rc3, v2.6.30, 2.6.28-14 and the stock Jaunty kernels before it. I have also tried the latest Karmic Alpha 3, but the results are the same. None of them seem to make the device show up or not show up any more or less frequently as far as I can tell.

I would say that on average, it shows up 60-70% of the time.

I'm running BIOS 3.05 (it seems 3.06 has been released, but the download link is broken - the changelog doesn't show anything related to this though). I've enabled everything possible in terms of internal components in the BIOS. The card's firmware is also the latest I think: R1D06

If there is anything else useful that I can provide, please let me know. I've attached a dmesg - this is when the card is not appearing.