function isEmail(s)	{   
	
	var i = 1;
	var sLength = s.length;

	while ((i < sLength) && (s.charAt(i) != "@")) {
		i++
	}
	if ((i >= sLength) || (s.charAt(i) != "@")) return(false);
	else i += 2;

	while ((i < sLength) && (s.charAt(i) != ".")) {
		i++
	}

	if ((i >= sLength - 1) || (s.charAt(i) != ".")) return(false);
	else return(true);
}


function emailc() {   

if (!(/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,4})+$/.test(profile.email.value))) 
    { 
        alert("Favor informar um email válido.") 
        profile.email.focus() 
        return (false) 
    } 
}