Shabbat with time dilation in space

I know there is some discussion in space/planets..

How would you keep shabbos in space?

The Rabbi I asked this shabbat pretty much said the same thing; and you go by Jerusalem time when in doubt.

However, afterwards I was thinking about the laws of relativity and space-time. So based on our current understanding of relativity.. time and space are not always "static".

Example being the faster you move in space the slower time goes.

http://en.wikipedia.org/wiki/Time_dilation

So if we start cruising off to other planets are very high speeds, time would "move slower".. and 25 earth-hours will not equal 25 hours in your spacecraft or whatever it may be.

So how long does shabbat last in space at "warp" speed?

Maybe I watch too much sci-fi.. thanks in advance.