Hi and welcome to Pet Talk!

I aksed a similar question some time ago and did some research and the answer was NO, jack russells are not generally good with cats or other small animals but as wolfsoul pointed out can learn to live with one.

However, you must never leave the two of them together without supervision. A warning from The Jack Russell Terrier Club of America: "raising a puppy with a cat does not guarantee the cat's lifelong safety."