function login(user, pass)
{
    var params = {};
    params['_ajaxcontrol'] = '';
    params['_ajaxact'] = 'login';
    params['_p1'] = user;
    params['_p2'] = pass;
    params['_p3'] = location.href;
    new Ajax.Request('../Login.aspx', {
        method: 'post',
        parameters: params,
        onSuccess: function(transport) {

            var ct = transport.getResponseHeader('Content-Type');
            var res = transport.responseText;
            if (ct.match(/text\/errormsg/))
            {
                alert(res);
            }
        },
        onFailure: function(transport) {
            alert('AJAX error');
        }
    });
}

function logout()
{
    var params = {};
    params['_ajaxcontrol'] = '';
    params['_ajaxact'] = 'logout';
    params['_p1'] = location.href;
    new Ajax.Request('../Logout.aspx', {
        method: 'post',
        parameters: params,
        onSuccess: function(transport) {

            var ct = transport.getResponseHeader('Content-Type');
            var res = transport.responseText;
            if (ct.match(/text\/errormsg/))
            {
                alert(res);
            }
        },
        onFailure: function(transport) {
            alert('AJAX error');
        }
    });
}