Description:
------------
In C and most other programming languages it is possible to parse NULL as a reference parameter to a function (a NULL-Pointer). In PHP i need to allocate a variable, that can be given to the function. So there is no way to parse a NULL-Pointer.

Reproduce code:
---------------
<?php

function bTest(&$paData)
{
  if (is_null($paData))
  {
    // cleanup
    return true;
  }
  // handle data
  return true;
}

bTest(NULL);

?>

Expected result:
----------------
Should work

Actual result:
--------------
Fatal error: Cannot pass parameter 1 by reference in ...