Trivial weird edge case creates perpetual motion

[Dabir]

I used magboots to build a wall across a running conveyor belt, placed a mechcomp component on it and anchored the component, then removed the wall. Doing this cursed the component to move in the direction of the conveyor belt forever, even though it was supposed to be anchored, to the point of leaping out of my hands when I picked it up. It happened twice so I'm pretty sure this is repeatable.