Preventing click event with Scriptaculous drag and drop

new Draggable('id', {
    onStart: function() {
        dPhoto = $('id');
        Event.stopObserving('id', 'click');
    },
    onEnd : function() {
        setTimeout("Event.observe('id', 'click', function() { location.href = 'url'; });", 500);
    },
    revert: true
});

new Draggable('tag',
    {
        revert:function()
        {
            $('tag').onclick = function(){return false;};
            setTimeout('$('tag').onclick = function(){return true;}','500');
            return true;
        }
    }
);

var click_func;
function onDragStart(drgObj,mouseEvent){
    click_func = mouseEvent.target.onclick;

    mouseEvent.target.onclick = function(e){
    	mouseEvent.target.onclick = click_func;
    	return false;
    }
}

function onDragStart() {
    Event.stopObserving(this.OBJECT,'click');
    Event.observe(this.OBJECT,'click',this.onDragEnd.bindAsEventListener(this));
}

function onDragEnd() {
    Event.stopObserving(this.OBJECT,'click');
    Event.observe(this.OBJECT,'click',this.PREVIOUSFUNCTION.bindAsEventListener(this));
}