function validertest() {
var obj=document.getElementById('nbpass')
var exp = new RegExp('^[0-9]{1,999}$','g')
if(exp.test(obj.value)) {
document.form1.pass_supp_submit.disabled = false
document.form1.submit()
}
else {
obj.style.color = 'red'
//alert("Nombre invalide")
}      
}

function test(plop) {
alert(plop);
}