I was driving my 06 XKR in cruise control and the gearbox fault light came on yesterday. When I turned the car on the light disappeared. I been driving the car normally every since no problems whatsoever. Do anyone knows what triggered this ? Is this normal ? Should I be worried and is the car fine ? Other than that its been one week of owning the Jag and I enjoy it despite the messages I seen pop up.

Random messages, lights that flash that shouldn't or don't flash that should are not problems but features engineered into British automobiles.

If it did not set a CEL/MIL and did not go into restricted mode it probably is one of the above features. If it reoccurs it may evolve into something to deal with.

Keep in mind that Jaguar's 'sealed for life' transmission philosophy means that it is sealed until opened for a rebuild, usually about 100k miles. Check out the debates on ATF change intervals.

With an '06 do you have any warranty coverage?

"Random messages, lights that flash that shouldn't or don't flash that should are not problems but features engineered into British automobiles."
Very clever test point. Thanks for the smile!