colorButton_enableMore

In config.js I've set colorButton_enableMore = true and the More Colors button appears in the colour drop down but when clicked it does nothing.

CKEDITOR.editorConfig = function( config )
{
   // Define changes to default configuration here. For example:
   // config.language = 'fr';
   // config.uiColor = '#AADC6E';
   config.width = '600';
   config.height = '400';
   config.font_names = 'Calibri/Calibri;' + config.font_names;
   config.colorButton_enableMore = true;
};

Any ideas please?