private void ShowFileVersions(int fileId)
        {
            if (fileId < 1)
            {
                return;
            }

            DocumentsExchangeModuleController moduleController =
                new DocumentsExchangeModuleController();
            String currentFileName = moduleController.GetOriginalFileName(fileId);
            lblCurrentFileDescription.Text = String.Format("Versions of file \"{0}\":", currentFileName);
            lstVersions.DataSource = moduleController.GetVersions(fileId);
            lstVersions.DataBind();
            multiView.SetActiveView(versionsPage);
        }