[Flow] Removing an object, that has references, leads to "Exception thrown without a stack frame in Unknow

[Christian Eßl]

Hi, 

I have defined a Page Object. Pages created with my model can have both a parent and multiple subpages, which are also "Page" objects. The idea is to form a simple pagetree. Also I have defined a simple boolean $root, to easily find the root page of my pagetree.

Here is the model:
http://pastebin.com/hR3zErsN

I created a SetupController with the following code, that should remove all pages from the repository, when it's called:

   $root = $this->pageRepository->findRoot(); // this returns the root page which has no other parent page
   $this->pageRepository->remove($root);
   $this->persistenceManager->persistAll();
   return 'success!';

When I try to call my SetupController, I just get a blank page and no pages were deleted. I looked in the apache error log and the following error was thrown:

PHP Fatal error:  Exception thrown without a stack frame in Unknown on line 0

This error is very vague, so I have no idea how to procceed from here. Any ideas what I did wrong?