Control buttons illumination

Have had my new 2010 Prius for 2 weeks now, just noticed that the mirror adjustment buttons and dash light roller do not have back lighting when the lights are on. All the rest of the buttons have back lighting when the headlights are on. I have searched the owners manual but do not see a list of switches that illuminate. Is this normal or do I bring it to the dealers attention. Minor problem I know but does bug me.

 

Please forgive my question, I had thought I did a thorough thread search but after posting the question now find an earlier discussion regarding this issue. The Mirror buttons apparently do not light up, I guess Toyota doesn't think anyone adjusts them in a darkend vehicle.