Please note that the initial BugReport was issued _after_ downgrading the Kernel from the problematic version 2.6.32-31 (squeeze-proposed-updates) back to version 2.6.32-30 (squeeze-stable), with which the problem does _not_ occur. Thus, for the 'Package-specific info', please refer to the version posted with Message #20, which was created with the correct Kernel version 2.6.32-31. Sorry for the confusion.