Why dont you just file down the knobs on the charger completely!? I did that after about 5 normal charges. Know this has been posted many times before, but I really think this will help preventing a loose plug. Mine slides in, out with no force at all. As long as you plug it all the way there will be no problems charging at all.

I agree this problem sucks overall, because a simple drop of the phone on the cable will rip the plug, shouldnt be.

Every phone I´ve owned have been nokia brand, and the n900 is far the best ever but its also the first one with a design flaw.