According to the TSB about this it's normal and the headlights are vented to help it clear naturally.
Info on the TSB should pop up in a search. I remember reading a lot about this two years ago on all the boards.
I asked my SA one time I was in and they check the lights and refused to change anything because of the TSB.
It only happened on the halogen lights. So far the Xenons have been dry.

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