title: Can PHP static methods legally have a visibility of protected or private?
body: <p>I realize that it's possible to define a static class method as private and protected in PHP. This allows for an instantiated class, or public static method to access it's own private/protected static methods.</p>
  
  <pre><code>protected static function jumpOver  ()
  </code></pre>
  
  <p>However I'm not sure if this is legal in the sense of OOP design. I can't find any real info stating it's ok to do this. I'm worried PHP may "patch" this in future versions if this is not a valid and break my scripts.</p>