Grappling hook ruling

[Rinnbaku]

Hey, can anyone tell me if there are rules for shooting a standard grappling hook (w/ spool of endless rope attached) out of a light crossbow? I know that there are specific tools in the peripheral books, but our party doesn't have access to a place to buy them right now. How should we treat the improvised version?

TTFN
Rinn ^_^'

[cakellene]

I think you just target a square with penalty on attack roll.