btDbvtBroadphase in very large worlds

[Ralith]

I'm interested in Bullet's capacity to handle effectively unbounded worlds (to the limits of floating point precision, of course). I've looked around the documentation and forums a bit and seen that using btDbvtBroadphase is the recommended way to do this. However, the descriptions of its behavior that I've seen (I'm not sure I've understood them correctly) suggest that it, in effect, scales an AABB to contain all dynamic bodies. If this is, in fact, how it behaves, would this result in the movement of one body to an extreme distance from the origin having a detrimental effect upon the simulation of bodies interacting near the origin?