overridding synchronized method with non-synchronized method should error

 
> From ###@###.### Thu Mar 14 16:46 PST 1996
> Return-Path: <###@###.###>
 
> - If a method is overridden in a subclass where:
> the superclass implementation defined the method synchronized,
> and the subclass omits the synchronized,
> the compiler does not complain. This is REALLY BAD.
> FURTHERMORE, the runtime seems not synchronize when the
> subclassed method calls super.method(). I have not conclusively
> established that this is happening, but it certainly behaved as
> though it was.