Not all WSDL files include the extensions required to create executable BPEL processes. The extensions are partner link types, properties, and property aliases.
Use the Participants view for automatic creation of partner link types.
You can use a Process Developer wizard to create partner link type definitions that are required for creating executable BPEL processes.
When you create new partner link types, Process Developer asks if you want to add them to an existing WSDL or create a new WSDL. If you create a new WSDL, it is automatically added to the project and catalogued in Interfaces. The WSDL contains only the partner link type definitions.
In addition, a wizard helps you create property and property aliases to be used for correlation sets. These extensions can be added to an existing WSDL or to a new WSDL.
For details, see
Partner Link Type
Adding Variable Properties and Property Aliases