Hello Kamalbabu,
after Migration of our ess applications from WebDynpro JAVA to Web Dynpro ABAP we have a problem that sounds similar to the one you descriped above.
In POWL the button 'details' (detail view) for leave request approval seem to have no function.
Because your post is a few years old, I guess you solved the problem and hope you can share your solution with us.
You will find more information about our specifc problem in this threat: http://scn.sap.com/message/15482063
Thank you.