ProjectInterface().RunReport for virtual documents

[mark.myers]

I am successfully using the RunReport method of the Project interface to generate RTF reports for packages however I would also like to do that for virtual documents, ie an element of stereotype "model document". The parameter to RunReport is expecting a PackageGUID and if I pass the GUID of the model document element it generates an error - not surprisingly. does anyone know if it is possible to run a report for a model document from the API?

Regards,
Mark.