gistfile1.php

// parent controller in global namespace
abstract class Controller_Application extends Controller {
  
  protected static $_vm = 'application';

  public function before()
  {
    $this->view = ViewModel::forge($this->_vm);
  }

}

// Request to this controller form module "admin" throw a OutOfBoundsException
// from ViewModel class

namespace Admin;

class Controller_Home extends \Controller_Application {
 ...
}