That's certainly one of the more difficult things to do. It's comparatively easy to remove reflections from skin, but if you had forgotten to take your polarizing filter with you and can't clone an unaffected area, then I'm afraid it's not possible.
Actually, Photohop can't "remove" anything. The effect of removing something is created by painting over unwanted spots.
If you can't clone, maybe masking the affected areas, correcting levels and enhacing contrast can do a little, but don't expect too much.
Edit: I found a 14-minute video tutorial here: Remove Glare and Add A Polarizing Effect
Hope it helps.
[Edited 2006-11-16 03:05:18]