Is there a way to open a window that has been glued shut (without breaking or removing window)?

I work for the Home Depot in the Door & Windows dept, and everyone's suggestions are valid, my main concern is how much glue was used & where. Anytime you glue together 2 bare ends of wood, very rarely will that joint break, it will usually break next to the where the glue was applied. I probably try a clothes steamer, and a putty knife, or you can try a heat gun, but you have to be careful not heat up the glass, because it will easily break. Maybe consult with a local Handy man, and see what they suggest.