PHP interaction with Word using COM problem

[cf]

Hello

I try to instantiate Word using COM in a PHP script, but I get this error:

Warning: (null)(): Unable to obtain IDispatch interface for CLSID
{000209FF-0000-0000-C000-000000000046}: ClassFactory ne peut pas fournir la
classe demandée in d:\program files\easyphp1-7\www\generateword.php on line
2
Cannot start MS Word

Here is my PHP Code
<?
$word=new COM("Word.Application") or die("Cannot start MS Word");
print "Loaded word version ($word->Version)\n";
$word->visible = 1 ;
$word->Documents->Add();
$word->Selection->Typetext("This is a test");
?>

I've looked for this CLSID in HKEY_CLASSES_ROOT and I can find it.
RPC and COM+ services are started, and I use PHP4 and Office 2003.
What can I do to make it work?
Thanks