Cannot update previous version of nt:file node

[Lubos and Alena Pochman]

I create nt:file node like:

       Node root = session.getRootNode();
       document = root.addNode(instanceName, "nt:file");
       document.addMixin("mix:versionable");  // Make document referencable
and versionable
       Node content = document.addNode("jcr:content", "nt:resource");
       content.setProperty("jcr:mimeType", "application/zip");
       content.setProperty("jcr:data", new
ByteArrayInputStream(zipContents));
       content.setProperty("jcr:lastModified", Calendar.getInstance());
       this.session.save();

Then I create a new version like:

       document.checkout();
       Node content = (Node)document.getPrimaryItem();
       content.setProperty("jcr:data", new
ByteArrayInputStream(zipContents));
       content.setProperty("jcr:lastModified", Calendar.getInstance());
       this.session.save();
       document.checkin();

Then I try to retrieve current version data (that works OK):

       node = this.session.getNodeByUUID(id);
       Property prop = node.getProperty("jcr:content/jcr:data");
       InputStream is = prop.getStream();

But then I try to retrieve previous version of the node, it fails with
"PathNotFoundException: jcr:frozenNode/jcr:content/jcr:data" exception when
calling getProperty("jcr:frozenNode/jcr:content/jcr:data"):

           Node document = this.session.getNodeByUUID(id);
           Version base = document.getBaseVersion();
           Version[] predecessors = base.getPredecessors();
            for (int i = 0; i < predecessors.length; i++) {
                      System.out.println(predecessors[i].getCreated() + ":
"
                              +
predecessors[i].getProperty("jcr:frozenNode/jcr:content/jcr:data").getLength());

How do I access and read properties of previous versions of a node?

Thanks, Lubos