HI Aakash
If you intend to use custom task then check following :
- Check if the "general task" indicator is maintained for custom task
Go to transaction PFTC Additional data->Classification-> Change
- Make sure that you execute swu_obuf transaction after step 1
Have you tried to refine the text of sap standard task, then you don't have to replace standard task with custom one.
PFTC
Edit -> Work item Text -> Redefine
regards
sandy