How to fix interior condensation on rear windshield?

See photo: http://i.imgur.com/kExvO.jpg

This happens when the weather gets colder. Interior condensation on the rear and front windshields.

Is this an indication that the seals of each need to be replaced?

Thanks

Had this with my Regal and it turned out the window was leaking and running down to the rear floorpan. (check passenger floor area for wetness) I sealed all around the outside trim with silicone and never looked back, after 5 years. It's good place to start and a cheap fix.

Good luck.