Sometimes the camera will focus on the glass rather than the object. My old camera had a button you could press to override the range detector and put the camera into an infinate view mode thus eliminating any problems from shooting through a window. Check your camera you might have a similar feature.

the camera is actully focused on the plane in most pictures its just that the sunlight made the reflection from the glass pretty obvious… and i didnt really know how to work around that at the time