Was wondering if anyone else has seen this problem:

The driver and passenger seats seem to pivot slightly resulting in an unsettling rocking sensation when I accelerate or brake. I've seen mention of this over on roadfly, where the problem has been fixed by either replacing or tightening the seat rails, but in some cases the problem comes back after a short time. Is this a common problem for recent Jags? If so, is there a definitive solution for fixing this for good?