Thanks Arun! I surely accept this as a better
solution.. It is working fine with all three
processors(Xalan-j 2.6.0, Saxon-SA 8.1.1 and MSXSL 4).

But I am still curious why my stylesheet is not
working same with all the three processors..

Either Xalan has a bug related to my XSL, or I am
using some non-standard feature(which I am not able to
figure out)..

Truly speaking I am a novice on this technology.
So I can't comment on the problem.
I just gave you another logic to try.

Its no point making life difficult. :-)
So I keep the logic as simple as possible.