My tag's added in the RB app do not sync right with RB on desktop.

I have tracks syncd with RB on my android.
I use the RB app on my android to order the tracks and also give them the right (my)tags.

When i sync the RB app back to the desktop the my tags are added to the RB desktop but they are not added to the comments filed of the track. 

I think this is a bug or is this the way it should work?