Add rating and parentalrating in DialogPVRInfo?

Hello Guys,
Is there a way to add “Rating” and “ParentalRating” items to the DialogPVRInfo screen in Confluence skin?

Currently I’ve tried:
* I have manually added values for those fields in the Epg11.db i.e. Ratings is 8 and ParentalRating is 14.
* I have manually edited the DialogPVRInfo.xml file adding the below code:

Code:
<item>
  <label>Rating:</label>
  <label2>$INFO[ListItem.Rating]</label2>
  <onclick>noop</onclick>
  <visible>!String.IsEmpty(ListItem.Rating)</visible>
</item>
<item>
  <label>Parental Rating:</label>
  <label2>$INFO[ListItem.ParentalRating]</label2>
  <onclick>noop</onclick>
  <visible>!String.IsEmpty(ListItem.ParentalRating)</visible>
</item>

Unfortunatelly nothing shows up in the PVRInfo screen for the given show.
However, this method works for other items like ListItem.imdbnumber or ListItem.Year or ListItem.Director which I also add manually to EPG11.db i.e. this works:

Code:
<item>
  <label>imdbnumber:</label>
  <label2>$INFO[ListItem.imdbnumber]</label2>
  <onclick>noop</onclick>
  <visible>!String.IsEmpty(ListItem.imdbnumber)</visible>
</item>

So it looks like even though there are values for Rating and ParentalRating, I am not able to show them in the PVR Info screen.
Any ideas are appreciated.

Regards,
Harry