function control()
	{
		var iChars = /\$|,|@|#|~|`|\%|\*|\^|\&|\(|\)|\+|\=|\[|\-|\]|\[|\}|\{|\;|\:|\'|\"|\<|\>|\?|\||\\|\!|\$|\./g;
		var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
        if (document.sign.uin.value.match(iChars))
			{
                alert ("Your username has special characters. \nThese are not allowed.\n Please remove them and try again.");
        	}
		else if(document.sign.uin.value == "")
			{
				alert('Please fill required fields "Username"');
			}
		else if(document.sign.pwd.value == "")
			{
				alert('Please fill required fields "Password"');
			}
		else if(document.sign.firstname.value == "")
			{
				alert('Please fill required fields "First Name"');
			}
		else if(document.sign.lastname.value == "")
			{
				alert('Please fill required fields "Last Name"');
			}
		else if((!document.sign.gender[0].checked)&&(!document.sign.gender[1].checked))
			{
				alert('Please fill required fields "Gender"');
			}
		else if(document.sign.email.value == "")
			{
				alert('Please fill required fields "E-Mail"');
			}
		else if(!filter.test(document.sign.email.value))
			{
                alert ('Pleade check your E-Mail');
        	}
		else if(!document.sign.situation[0].checked&&
				!document.sign.situation[1].checked)
			{
				alert('Please fill required fields "Membership Type"');
			}
		else if(document.sign.img.value != document.sign.imgh.value)
			{
				alert('Please check right image code ');
			}
		else
			{
				document.sign.submit();
			}
		
	}