Thanks anon848905 and marvinson for valuable reply. Yes, in my text the Devanagiri Danda and Devanagiri double danda (used in earlier text for denoting paragraph ending) was used as Alphabetic Characters. This caused the problem. Thank you for the solution
NB: I apologize for the late reply. After I posted the question, today only could see the web portal. it might be good to get an email if our questions are answered by some one
Blessings
binoy