View Details for smmActivities Table is not working

Hello All,

In standard system, when i goes to Project management Module>All Projects>Plan>WorkBreakDownStructure>Line details>General>Activity Number and then right click on activity number then click view details it gives me warning that Unable to View details, no form exists for table ‘ProjTaskCostView’.

In my smmActivities Table there are formref property is already set but its trying to find form on projTaskCost view because there is standard relation available with it.

what to do?Is this a standard bug?