Not getting Pop-Up for rejection in CRM Worklist

Hello all,

I am working on CRM workflows and we are on EHP 6 where for Generic User Decision Task we can give Justification as required or mandatory.

When I create a task with approve and reject buttons and make Rejection Reason as mandatory on Reject it works fine in SBWP inbox ,when I try to execute same from CRM Worklist I wont get the POP-UP to give rejection reason.

Please let me know how to get the popup for rejection in CRM worklist.