I read some where that when the star sign was first worked out it was so long ago, that the star sign might not be the same any more.
can any one tell me if this true or not

True. Starts orbit the center of galaxies at different speeds, so they may be in different places, or even not there anymore. It may take a few hundred years for there to be a noticable difference in placement of the stars, but there is.

The earth precesses in its rotation, which is a fancy way of saying that it wobbles while it rotates, which impacts the location of the stars in the night sky.  The effects are slow, like jallious says, and can be demonstrated in the location of a "north star" (in the northern hemipshere).  The north star now is Polaris.  5000 years ago it was a different star, Thuban, in the constellation Draco.  The whole period of changing locations for the north star takes about 26000 years:



I think - my astronomy skills are stronger than my astrological ones - is that the oft mentioned (in the 60's) Age of Aquarius is a result of precession.  The vernal equinox (the point when Spring starts) is located in Pisces; 2000 years ago it was in Aries.  In the future (500 years, I think) it will move into Aquarius.

I thought that the North Star was Sirius (also the brightest ever star known), but I maybe wrong there.

http://www.accessnewage.com/articles/astro/ageaq1.htm

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Ramendra
jaipur