I am attempting to use the bulk document importer and the FileWithIndividualMetadasSourceNode to load custom metadata for many files in the filesystem. I have tried several formats for the properties documents listed there. Right now I have .properties files with contents like this:

dc\:title=Social media marketing
book\:bookEdition=
creativework\:publisher=Pearson
creativework\:keywords=Internet advertising|Internet marketing|Online social networks|Social media
creativework\:author=Tuten, Tracy L.|Solomon, Michael R.
creativework\:copyrightYear=2013
book\:isbn=9780132551793

But the importer log reports errors like this:

DEBUG : Unable to create leaf document for /Users/shuwig/prod_data/isbnpdfs/9780071748469.pdf:org.nuxeo.ecm.core.api.model.PropertyConversionException: Property Conversion failed from class java.lang.String to class [Ljava.lang.Object;: /creativework:author

The related parts of the schema simply look like:

   <xs:simpleType name="textList">
     <xs:list itemType="xs:string"/>
   </xs:simpleType>
    ...
   <xs:element name="author" type="lt:textList"/>

and everything about my document type works fine except for importing in bulk.

Is it possible to import multi-value metadata elements via the bulk importer? How can I do this without receiving the above error?