function check_mail(email) {
	invalid = " /:,;";
	if("email" == "") {return false}
	for(i=0; i< invalid.length; i++) {
		bad = invalid.charAt(i);
		if(email.indexOf (bad, 0) != -1) {return false}
	}
	at = email.indexOf("@", 0);
	if( (at == -1) || (at == 0) ) {return false}
	if(email.indexOf("@", at+1) != -1) {return false}
	period = email.indexOf(".", at);
	if( (period == -1) || (period == at+1) ) {return false}
	if(period+3 > email.length == -1) {return false}
	return true;
}

function zapisz(form) {
	if (!(check_mail(form.email.value))) {
		alert('Podaj poprawny adres e-mail');
		form.email.focus();
		form.email.select();
		return false;
	}
	else {
		return true;
	}
}