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This sounds like a scene from Josh Kirby... Time Warrior!
, it was a low-budget, plothole-ridden science fiction miniseries, that I really enjoyed.
The title character has the power to manipulate time in some way every 12 hours (relative to himself), in the scene you saw he aged the prison bars by thousands of years. Go watch it if you can find it.
EDIT: Found it! The described scene is found 6:50 into this video
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I remember one scene. But i have no idea where this scene came from. It involved a teen-looking dude in a cell. And some other guy (for some reason i think he looked like Dumbledore). This dude grabs iron bars and just squeeses them hard. Then there was some cheap effects (it was something old, many years before Potter mind you) and iron bars suddenly became so rusty, that nearly turned into dust. And this dude bent them, so that they could escape the cell. That other guy said that it's his power that can speed up time of items he touches or something. That's all i can remember.