Thanks a loooooot!!!!!
My problem have been solved....

The Solution Suggested by Unbeliever is working fine....
When I tried with the solution by jerardfjay , it gives me the following error : Segmentation fault(coredump) .. Could you please tell me why ? I am using AIX 5.

The solution with sed by reborg is also working fine.. but it fails , if more that one \n is there in a single line. It appends the first with second..and so on... any way could you please explain the code.. if you don't mind

Thanks once again
Shihab