Reuse of the server extensions

Hi all,

I want to extent the functionality of the NonXML indexer providing support for the mimetypes that are not supported by this extension. For instance I would like to implement the extension that will handle the
application/powerpoint mime type that extracts the metadata and content from the power point documents and store it in the same way as it’s done for the other mimetypes. For all other types I want to pass the call to the NonXMLIndexer extension (invoke its putBinary/putText function) Is there any documented way of such a chaining of the server extensions (i.e. invoking the code of the existing extension from my shadow function)?

Thanks in advance,