Description:
------------
PHP5.2 + Apache 2 + Microsoft DRM SDK installed. 
Error with using DRM SDK COM methods.


Fatal error:  Call to undefined method 

Reproduce code:
---------------
$headerObj = new COM("Wmrmobjs.WMRMHeader") or die("Unable to instanciate WMRMHeader");

//object was created successfully

com_print_typeinfo($headerObj);

//object methods are shown successfully

/*
class IWMRMHeader2 { /* GUID={44F7DFDA-C7D1-4C7F-83D2-73BA3EAED9FA} */

...

/* DISPID=8 */
	function Sign(
		/* VT_BSTR [8] [in] */ $bstrPrivKey 
		)
	{
		/* method Sign */
	}

...
}
*/


//try to use method Sign():

$headObj->Sign($contentserverpubkey);

//Fatal error:  Call to undefined method stdClass::Sign()


Actual result:
--------------
Fatal error:  Call to undefined method stdClass::Sign()