Comment 2 for bug 469376

I have pretty much come to the conclusion this is a udev problem. The only way the hso driver could have been called into play to replace SCSI emulation for USB on the ZeroCD is via a udev action, and this udev action is clearly where the breakage is located.

Done properly the ZeroCD in the Option/AT&T Quicksilver 3G Modem should be disabled long before SCSI emulation for USB is invoked. For a working example of how this should be performed see the Ozerocdoff package at http://pharscape.org/Quicksilver.html. The readme file in the tarball is quite informative as to how and when disabling the ZeroCD should be performed by udev and why it must be done that way.

For now, as the Ozerocdoff package exists and works, the current Ubuntu 9.10 default udev behavior for this device should be disabled allowing the ZeroCD to remain untouched and automount as a CDROM ( revert back to what was done for this device in 9.04 ). Then interested users can elect to apply the Ozerocdoff package and get the proper behavior rather than the total system lockup, requiring a hard power cycle to clear, which is all we can get now.

If someone whats to take a different view, I am willing to listen, but at the moment this is how I view this bug and how to fix it.