Error: access of undefined property URL_request

1

Hi

I am trying to get this email contact form to work but I get this error:
access of undefined property URL_request

ContactBoxText.as:
//package {
//code
//import etc.

	var timer:Timer;
	var var_load:URLLoader = new URLLoader  ;
	var URL_request:URLRequest = new URLRequest("send_email.php");
	URL_request.method = URLRequestMethod.POST;

	function sendemail(e:MouseEvent):void
	{
		if ( inputtext1.text == "" || inputtext2.text == "" ||
		inputtext3.text == "")
		{
			errortext.text = "Please fill up all text fields.";
		}
		else if ( !validate_email(inputtext2.text) )
		{
			errortext.text = "Please enter the valid email address.";
		}
		else
		{
			errortext.text = "sending...";

			var email_data:String = "name=" + inputtext1.text
			   + "&email=" + inputtext2.text
			   + "&message=" + inputtext3.text;

			var URL_vars:URLVariables = new URLVariables(email_data);
			URL_vars.dataFormat = URLLoaderDataFormat.TEXT;

			URL_request.data = URL_vars;
			var_load.load( URL_request );
			var_load.addEventListener(Event.COMPLETE, receive_response );
		}
	}

	function reset(e:MouseEvent):void
	{
		inputtext1.text = inputtext2.text = inputtext3.text = "";
	}

	function validate_email(s:String):Boolean
	{
		var p:RegExp = /(\w|[_.\-])+@((\w|-)+\.)+\w{2,4}+/;
		var r:Object = p.exec(s);
		if (r == null)
		{
			return false;
		}
		return true;
	}

	function receive_response(e:Event):void
	{


		var loader:URLLoader = URLLoader(e.target);
		var email_status = new URLVariables(loader.data).answer;

		if (email_status == "yes")
		{
			errortext.text = "Success! Your message was sent.";
			timer = new Timer(500);
			timer.addEventListener(TimerEvent.TIMER, on_timer);
			timer.start();
		}
		else
		{
			errortext.text = "Failed! Your message cannot sent.";
		}
	}

	function on_timer(te:TimerEvent):void
	{
		if (timer.currentCount >= 10)
		{
			inputtext1.text = inputtext2.text = inputtext3.text = "";
			timer.removeEventListener(TimerEvent.TIMER, on_timer);
		}
	}

}

}