var WatermarkLabel = Class.create({ initialize: function (id) {
    this.textbox = $(id); this.text = ''; var labels = $$('label[for="' + id + '"]'); if (labels.length) { this.text = labels[0].innerHTML; Element.hide(labels[0]); }
    this.textbox.observe('focus', this.focus.bindAsEventListener(this)); this.textbox.observe('blur', this.blur.bindAsEventListener(this)); this.textbox.observe('value:changed', this.change.bindAsEventListener(this)); this.blur();
}, focus: function (event) {
    if (this.empty)
        this.textbox.value = ''; this.empty = false; this.textbox.removeClassName('empty');
}, blur: function (event) { if (this.textbox.value == '') { this.textbox.value = this.text; this.textbox.addClassName('empty'); this.empty = true; } }, change: function (event) { this.empty = (this.textbox.value == ''); this.textbox.value == '' ? this.blur(event) : this.focus(event); } 
});