Problem inline label (jQuey)

Hi,

I’m building my new theme and I’ve a problem. I use jQuey to display the input’s label into the input :

this.label2value = function(){	

	var inactive = "inactive";
	var active = "active";
	var focused = "focused";

	$("label").each(function(){
		obj = document.getElementById($(this).attr("for"));
		if(($(obj).attr("type") == "text") || (obj.tagName.toLowerCase() == "textarea")){
			$(obj).addClass(inactive);
			var text = $(this).text();
			$(this).css("display","none");
			$(obj).val(text);
			$(obj).focus(function(){
				$(this).addClass(focused);
				$(this).removeClass(inactive);
				$(this).removeClass(active);
				if($(this).val() == text) $(this).val("");
			});
			$(obj).blur(function(){
				$(this).removeClass(focused);
				if($(this).val() == "") {
					$(this).val(text);
					$(this).addClass(inactive);
				} else {
					$(this).addClass(active);
				};
			});
		};
	});
};
$(document).ready(function(){
	label2value();
});

But, the problem is, if, when I submit the comm, there’s not a website url, WP uses the label as an URL (http://YourWebsiteURL).

How can I solve this problem ?

Thanks ^^