function checkFields() {
missinginfo = "";
if (document.formulario.name.value == "") {
missinginfo += "\n     -  Nombre";
}
if ((document.formulario.from.value == "") || 
(document.formulario.from.value.indexOf('@') == -1) || 
(document.formulario.from.value.indexOf('.') == -1)) {
missinginfo += "\n     -  Correo Electronico";
}

if (missinginfo != "") {
missinginfo ="_______________________________________\n" +"ERROR, Informacion requerida invalida:\n" +
missinginfo + "\n_______________________________________" +"\nIngrese los campos requerida e intentelo de nuevo!";
alert(missinginfo);
return false;
}
else return true;
}