Yii framework failed to open stream

Bin ich mit dem Yii-framework und erstellen Sie Benutzer-Registrierung Seite. Alles scheint gut zu funktionieren, aber wenn ich hochladen will user Bild, bekomme ich eine Fehlermeldung:

include(Self.php) [<a href='function.include'>function.include</a>]: failed to open stream: No such file or directory

Hier ist mein SiteController-code:

public function actionRegister()
{
    $model=new RegisterForm;

    //uncomment the following code to enable ajax-based validation

    if(isset($_POST['ajax']) && $_POST['ajax']==='register-form')
    {
        echo CActiveForm::validate($model);
        Yii::app()->end();
    }

    if(isset($_POST['RegisterForm']))
    {
        $model->attributes=$_POST['RegisterForm'];
        if($model->validate())
        {
            $user = new User;
            $user->username = $_POST['RegisterForm']['username'];
            $password = $_POST['RegisterForm']['password'];
            $salt = Security::GenerateSalt(128);
            $user->password = hash('sha512', $password.$salt);
            $user->question = $_POST['RegisterForm']['question'];
            $user->answer = $_POST['RegisterForm']['answer'];
            $user->salt = $salt;
            $user->email = $_POST['RegisterForm']['email'];
            $user->fullname = $_POST['RegisterForm']['fullname'];
            $user->birth = $_POST['RegisterForm']['birth'];
            $user->avatar = CUploadedFile::getInstance($model,'image');
            $user->avatar->saveAs('/images/users.test.jpg');
            $user->about = $_POST['RegisterForm']['about'];
            $user->signup = date('d/m/y');
            $user->login = date('d/m/y');
            $user->save();
        }
    }
    $this->render('register',array('model'=>$model));
}

Hier ist mein RegisterForm Modell code:

<?php
class RegisterForm extends CFormModel
{
[.....]

 public $avatar;

[.....]

    public function rules()
    {
        return array( 

[......]

            array('avatar', 'file', 
                                'types'=>'jpg, gif, png', 
                                'maxSize'=>1024 * 1024 * 2,
                                'tooLarge'=>'The file was larger than 2MB. Please upload a smaller file.',
                                'wrongType'=>'Please upload only images in the format jpg, gif, png',
                                'tooMany'=>'You can upload only 1 avatar',
                        'on'=>'upload'),

[......]

}

Ansicht:

<div class="row">
    <?php echo $form->labelEx($model,'avatar'); ?>
    <?php echo CHtml::activeFileField($model, 'avatar'); ?>
    <?php echo $form->error($model,'avatar'); ?>
</div>