var myrules = {
	'form textarea' : function(element){
		element.onclick = function(){
			if(this.value == 'Ihre Nachricht...') this.value='';
		}
	},
	'a[rel="external"]' : function(element){
		element.onclick = function(){
			this.target = "_blank";
		}
	}
};

Behaviour.register(myrules);