Get-CrmDataPackage doesn't include column in Schema output

Hi @abvogel 
in our case, the FetchXML passed to Get-CrmDataPackage includes a column that isn't included in the output schema. The column in question is of the type 'optionsetvaluecollection', but it appears XmlSchemaBuilder.GetFieldNodeType doesn't support optionsetvaluecollections. Is this an oversight, or is it deliberate?
Thanks,
Morten