Error in Standard Business Object BUS2012

Hi Friends..

Iam using standard business object BUS2012 for purchase order creation workflow.

while creating PO the workflow need to be triggered.

But i got an error message in BUS2012 thatswhy the workflow was not triggered while creating PO.

i got the following error

"Basic IDOC type PORDCR02 is unknown"because of this error the workflow was not getting triggered..

so how can i solve this problem..

Thanks

Gowrishankar