public function test__toStringFrozen()
 {
     $tc = new HTML_QuickForm2_Element_Captcha_TextCAPTCHA(null, null, array('captchaType' => 'Word', 'phrase' => '123'));
     $tc->setSession(new HTML_QuickForm2_Element_Captcha_Session_Mock());
     $tc->toggleFrozen(true);
     $html = (string) $tc;
     $this->assertContains('one two three', $html);
 }