function clear_field(obj, label)
{
    if (obj.val() == label.val()) {
        obj.val("");
    }
}
function fill_field(obj, label)
{
    if (obj.val() == "") {
        obj.val(label.val());
    }
}
$(document).ready(function(){
    var passwd = $("#password"),
        passwd_label = $("#l_password"),
        username = $("#login"),
        username_label = $("#l_login");
    username.focus(function(){
        clear_field(username, username_label);
    });
    username.blur(function(){
        fill_field(username, username_label);
    });
    passwd_label.focus(function(){
        passwd_label.hide();
        passwd.show().focus();
    });
    passwd.blur(function(){
        if (passwd.val() == ""){
            passwd.hide();
            passwd_label.show();
        }
    });
    $("#auth_form").submit(function(){
        if (username.val() == username_label.val()) username.val('');
        if (passwd.val() == passwd_label.val()) passwd.val('');
        return true;
    });
});