[Twisted-Python] Jellying Decimals?

[Jasper]

I'm trying to Jelly decimal.Decimals, using Twisted 2.4.  I've tried a 
few approaches, such as deriving my own Decimal class from 
decimal.Decimal, pb.RemoteCopy, and pb.Copyable, but no luck.

Is there an easy way to do this, without patching twisted itself?  Worse 
case I could always fall back on passing strings across the wire I 
guess, but that's not very enticing. :-/

-Jasper