One wonders what you can possibly do to a knife switch to make it fail to open.
Just a shot it the dark..maybe the plastic "clips" that move the contact blades break, leaving the blade fully or partially closed?
Once again, just like the Xmas light recall,
they don't give any details of what the bloody problem is caused by!! Very annoying.
edited to add link
[This message has been edited by mxslick (edited 12-19-2006).]