WIP ACCOUNTING CLASS FOR AVERAGE COSTING ORGANIZATION WITH PROJECT REFERRENCE ENABLED HAVE TO BE ASS

 We are working for India implementation which require Average costing method. I am facing the problem of my WIP Job are not able to be created, Planned Order for Finished goods not able to be imported into WIP module and WIP jobs not getting created through ATO order process becuase of the error as below:

"The WIP accounting class... that you have chosen does not have an enabled
association with a Cost Group. This association is required in the case of an average costing
organization with project reference enabled. "

Then we assigned the Default WIP Accounting class for that organization Cost Group and the issues cleared. We used to do this for Projects Cost group since Project assignment with the organization requires this. But the assignment of default WIP accounting class with the default cost group without Project associated job orders require this? Can someone tell if this is required in R12.1.1 OR are we missing any setups?