SoapUI Pro Does not provide access to data classes that extend a base class

Using SoapUI Pro to test web services developed with .NET that use overloaded classes to define the input data, the only class visible in the Request editor is the base class.

The WSDL (attached) has two classes ComponentProdOfferPrice and CompositeProdOfferPrice that need to be used to provide the input data to updateProductOfferingPrice. The base class is ProductOfferingPrice.

The Web services I am attempting to validate make extensive use of this feature. The attached WSDL file has been reduced to one interface that exhibits the issue.

This problem is preventing significant testing on the web services.