function login() 
{
	var loginForm = document.getElementById("loginForm");
	if (loginForm.user.value == "") {
		alert("Please enter your user name.");
		return false;
	}
	if (loginForm.pass.value == "") {
		alert("Please enter your password.");
		return false;
	}
	var submitForm = document.getElementById("submitForm");
	submitForm.user.value = loginForm.user.value;
	submitForm.md5pass.value =
		hex_md5(loginForm.challenge.value+loginForm.pass.value);
	submitForm.submit();
};