Were you focusing on the eye? If so, its front focused. This might also be caused by focus being messed up by the glass.
If you change cameras, focus will not be the same, it might back focus, or be perfect.
Test the lens on a subject that allows complete control of the area in focus, like a brick wall at 90 degrees. You must know exactly where the camera tried to focus, and the little red square does not guarantee it.
If its off noticeably, ask Canon to calibrate the lens on their reference 60D.