$username="myusername";
$password="mypassword";
$browserRT = new &SimpleBrowser();
$browserRT->useCookies();
$browserRT->useFrames();
$browserRT->get('https://admin.mywebsite.com/');
$browserRT->setFieldByName('user', $username);
$browserRT->setField('password', $password);
$browserRT->click('Login');