Automatic Magnetism in 2.49

If this is a commonly asked question, I’ve failed to find it in the forums.

I’m having a problem using 2.49 (I’ll get around to upgrading eventually:p) where if I resize an object in edit mode, it either snaps onto or somewhere around (in a jumbled formation) the object which serves as the walls, ceiling and floor of my room model. I’m familiar with similar behavior from using the snap tool but this problem occurs even when snap is disabled. “Proportional edit” is off and “rotation/scaling pivot” is set to median point as usual so I can’t see where I’ve gone wrong. Any advice much appreciated.

You really must add a link to where users can download your blend file that shows this behaviour.
Host your blend here http://www.pasteall.org/blend/

Sorry, internet problems made this post belated. The problem’s been solved in the time being though. Thanks a lot for your advice.