public function testMultipleCallbackRules()
 {
     $this->setExpectedException('fValidationException');
     $_GET['foo'] = 'Thi';
     try {
         $v = new fValidation();
         $v->addCallbackRule('foo', array($this, 'measure'), 'Please enter something four characters long');
         $v->addCallbackRule('foo', array($this, 'measure2'), 'Please enter something two characters long');
         $v->validate();
     } catch (fValidationException $e) {
         $this->assertContains('Foo: Please enter something four characters long', $e->getMessage());
         throw $e;
     }
 }