var SuggestField = Behavior.create({
	initialize: function(options) {
		this.options = options;
	},
	onfocus: function(e) {
		var element = e.element();
		if(element.value == this.options.suggest) element.value = '';
		else if(element.value == '') element.value = this.options.suggest;
	},
	onblur: function(e) {
		var element = e.element();
		if(element.value == '') element.value = this.options.suggest;
	}
});

Event.addBehavior({
	'input#username': SuggestField({ suggest: 'Username' }),
	'input#password': SuggestField({ suggest: 'Password' })
});