Description:
------------
The COM Application 'myApp' (some properitary inhouse product) throws 'com_exception' if a PHP5 script tries to execute a SET method of given object. Other applications written in C/C++, Python and Excel VBS work fine. 

IDL of myApp:
  [id(0x00000038), propget]  VARIANT DocumentParameterValue(BSTR parameterName);
  [id(0x00000038), propput]  void    DocumentParameterValue(BSTR parameterName, VARIANT rhs);

Reproduce code:
---------------
<?php
  $obj = new COM("myApp.Document");
  echo $obj->DocumentParameterValue('project');                 // get (ok !)
       $obj->DocumentParameterValue('project', strval('ZONK')); // set (fails !)
?>

Expected result:
----------------
Output value of parameter 'project' and set it to string 'ZONK'.

Actual result:
--------------
First 2 lines execute ok, but the third line fails with following error:

Fatal error: Uncaught exception 'com_exception' with message 'Error [0x8002000e] Invalid number of parameters.'