Laravel 4 - Catch Error异常无效

I have the following code in my controller:

public function edit($id)
{       
    try
    {
        $post = Post::findOrFail($id);

        $this->layout->content = View::make('edit.press');
    }       
    catch(ModelNotFoundException $e)
    {
        return Redirect::to('press');   
    }

}

when I actually go to the page /press/1/edit & id 1 is not in there I get an exception error : ModelNotFoundExceptio , Laravel error pages shows up and its not redirecting to the press page again? why please help me