purtroppo non funziona! :-( ecco il codice che uso per chiarezza:

$htmlFile = 'file.htm';
$file = fopen($htmlFile,"r");
$size = filesize($htmlFile);
$html = fread($file, $size);
fclose($file);
$html= stripslashes($html);
$html= html_entity_decode($html);
// $html contains the HTML to be turned into PDF

$pdf=new HTML2FPDF();
$pdf->AddPage();
$pdf->WriteHTML($html);
ob_start();
$pdf->WriteHTML(ob_get_contents());
ob_end_clean();
$pdf->Output();
$pdf->Output('doc.pdf');