addSendMailBtnEvent = function () {
    $('contact_form').addEvent('submit', function(e){
        var err = 0;
        // Verification de base des champs de formulaires indispensables (*)

        if($('contact_email').value == "")
        {
            $('email_lbl').style.color = 'red';
            $('email_lbl').style.fontWeight = 'bold';
            err++;
        }else{
            $('email_lbl').style.color = 'black';
            $('email_lbl').style.fontWeight = 'normal';
        }

        if($('contact_message').value == "")
        {
            alert("Veuillez renseigner les champs obligatoires !\nPlease fill the required fields !")
            err++;
        }

        var valid_mail = /^[a-z0-9._-]+@[a-z0-9äöüÄÖÜ.-]+\.[a-z]{2,4}$/i;

        if(($('contact_email').value != "") && ($('contact_email').value.search(valid_mail) == -1))
        {
            err++;
            $('email_lbl').setStyles({color : 'Orange', 'font-weight' : 'bold'});
        }

        return (err == 0);
    });

}

aFunctions.push(addSendMailBtnEvent);