tried to jump start jag xj8 turns over won't start

In your case, I know that with american cars, if the starter turns but the engine doesnt start, it frequently is because there is no fuel coming, or no spark going to the distributor from the coil. You can check for the spark by removing a spark plug wire at the spark plug end, then while wearing a glove so not to get a shock, position the end of the wire toward any metal in a dark area to see if there is any spark when another person turns the starter with the key/ignition. Hope this helps. I have a simillar problem with my 99 Jaguar XK8, the battery drained, so after failing to start with a jump, I recharged the battery then reinstalled it, then tried to start it, but though it goes to system check on dash, the starter won't turn, this never happened before when drained battery was jump started, it usually started, but now nothing I try gets the starter to turn. Please let me know what to do or if there is a specific procedure that must be followed with Jaguars in such instances where a battery was drained or removed then re-installed. Thanks alot much appreciated.