There is no real solution. Most of us consider it a design flaw and Kawasaki never redesigned it to fix the flaw- they only created a stronger spring to help avoid/prevent the issue. Rarely would you ever get stranded because you will typically have plenty of notice the condition is starting. Some people will never have the issue. Some will have occasional signs. Others will have big issues. It depends on lots of factors- how the bike is stored and protected, weathering, how often the ignition is used, how often the key knob is removed, if anything was ever sprayed into the mechanism, etc.
I am not terribly worried, I have only seen a touch of it twice in 8 years and thousands of uses- and both times it snapped out of it easily by pressing down hard and releasing it quickly by sliding my thumb off the knob. If that started happening often, then the writing is on the wall. I have had a zillion times more problems with the gas cap corrosion issue- and that almost left me stranded more than once. Other people seem to pick up tire nails every year and get stranded
But if you are worried, follow gPink's link, above to BDF's emergency work-around cable.
UPDATE: Turns out this is not what he is talking about at all