--- linux-source-2.6.12-2.6.12/drivers/parport/parport_serial.c	2005-06-17 21:48:29.000000000 +0200
@@ -418,10 +419,13 @@
 		return err;
 	}
 
-	if (parport_register (dev, id)) {
+	err = parport_register (dev, id);
+	if (err < 0) {
 		pci_set_drvdata (dev, NULL);
 		kfree (priv);
 		return -ENODEV;
+	} else if (err) {
+		priv->num_par = 0;
 	}
 
 	if (serial_register (dev, id)) {