setReadOnly bug either in code or docs

The
documentation
states that “The read-only property does not prevent changing the value of a component programmatically”, but looking in the source AbstractField.setValue(Object newValue, boolean repaintIsNotNeeded) a ReadOnlyException is thrown when somebody calls setValue().
I thought that read only is only a matter of rendering the component so the user can not change the value on the client side.
Is this a bug in the code or in the documentaion?


Thomas