I have contact lookup in task. If I choose contact then it should show only related contacts to Account. I put the filter condition as follows <br/> Activity: Related To ID equals Contact: Account ID The above condition works fine if I create task from Account related list as Related To ID matches the Account Id whereas if I try to create task from Opportunity related list its not showing any contact as Related To ID in this case is Opportunity Id not Account Id. How to overcome this?