function validate_empty(form, valor, campo, msg)
{
 if (valor == "")
 { alert(msg); document.getElementById(campo).focus(); return 1; }
}

function validate_measure(form, msg)
{
 if(document.getElementById('c1').checked == false && document.getElementById('c2').checked == false)
 {alert(msg); return 1;}
}


function Validate(form){
//E-Mail
 if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(form.temail.value)){
   //nothing
 } else {
   alert("The mail address is invalid"); form.temail.select();form.temail.focus();
   return;
 }
 if(validate_empty(form,form.tname.value,"tname","Please, specify your name")==1){return;}
 
	if(document.getElementById('codeval2').value == ""){
		alert("Please, write code validation"); document.getElementById('codeval').focus();return false;
	}
	
	if(document.getElementById('codeval2').value.toUpperCase() != document.getElementById('codv').value.toUpperCase()){
		alert("The code you have written is invalid, please try again"); document.getElementById('codeval').focus(); return false;
	} 
 
 if(validate_empty(form,form.mensaje.value,"mensaje","Please, specify message")==1){return;}

// send form
form.submit();
}