var rolloverButtonsBehaviour = {

	'div.rollover_buttons': function(el) {

		var updiv = $(el.parentNode);

		updiv.observe('mouseover',function(evt) {

			this.select('.mouseshow').invoke('setStyle',{'visibility':'visible'});

		}.bindAsEventListener(el));

		updiv.observe('mouseout',function(evt) {

			if (evt.relatedTarget && evt.relatedTarget.up && evt.relatedTarget.up('#' + updiv.identify()))
				return;
			
			this.select('.mouseshow').invoke('setStyle',{'visibility':'hidden'});

		}.bindAsEventListener(el));
	}
}

Behaviour.register(rolloverButtonsBehaviour);