/* validates email */
function validate_email(val) {
    var reg = /^$/;
    if(reg.test(val))
        return true;
        
    reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
    return !(reg.test(val) == false);

}