PHP4 no longer uses the com_load function anymore. Instead, you can use the COM object:

<?
$word=new COM("word.application") or die("Cannot start word for you");
print "Loaded word version ($word->Version)\n";
$word->visible =1;
$word->Documents->Add();
$word->Selection->Typetext("Dit is een test");
$word->Documents[1]->SaveAs("burb ofzo.doc");
$word->Quit();
?>

If you are still using PHP 3, then you can use the com_load function.