I dont think JKC has the adoption to support a JKC/BTC only exchange. LTC barely has that level of adoption.
If you look at the major exchanges, almost all the trading pairs are with BTC now.
example:
https://bter.com/Even BTC-E is only introducing BTC pairs now:
https://btc-e.com/I believe the days of matching with LTC may be over with the exchanges. Good or bad, that just seems to be the direction it is going.