Steps to reproduce:
1. Go to Catalog component (https://demo-trunk.ofbiz.apache.org/catalog/control/main)
2. Click on Products from submenu.(https://demo-trunk.ofbiz.apache.org/catalog/control/FindProduct)
3. Provide search preference and click on Find button.
4. Click on any Product Id link (https://demo-trunk.ofbiz.apache.org/catalog/control/EditProduct?productId=WG-9943).
OEM Party Id is a text field with no look up. A user needs to know the correct partyId else it will give an error due to the violation of "Referential Integrity".