function vanishing_input(obj){
	obj.original_value = obj.value ;
	obj.original_color = obj.style.color ;
	obj.style.color = '#999' ;
	obj.onfocus = function(){
		if( this.value == this.original_value ){
			this.value = '' ;
			this.style.color = this.original_color ;
		}
	}
	obj.onchange = obj.onblur = function(){
		if( this.value == '' || this.value == this.original_value ){
			this.value = this.original_value ;
			this.style.color = '#999' ;
		}else{
			this.style.color = this.original_color ;
		}
	}
}