Thank you Modak...
Your Reply really helped to resolve my issue...Initially I was using "Activity step" rather than "Decision step". I have just change the Step and done accordingly...
My problem solved..
Can You answer my one another question..I have configured the Tcode: SWFVISU to replicate the WI to the SRM Portal. Here I have added my task (Custom task copied of standard decision task) ..Visualization type Webdynpro ABAP.
Application: WDA Application name
Namespace: SAP
DYNPARAM : ______________
I don't know how to pass dynamic parameter to the WDA opening from WI on Portal UWL.
Thanks
Chandan