Is it valid to declare more than one XamDockManager control in a window? If not can you help me implement this. I currently have something like what's defined below:

<window>
  <grid>
    <igDock:XamDockManager x:Name="_dockManager">
      <igDock:XamDockManager.Panes>
        <igDock:SplitPane x:Name="_workspace">
          <igDock:TabGroupPane x:Name="_workpane">
            <igDock:ContentPane x:Name="_measurements">
              <TreeView />
            </igDock:ContentPane>
            <igDock:ContentPane x:Name="_wallscore">
              <TreeView />
            </igDock:ContentPane>
          </igDock:TabGroupPane>
        </igDock:SplitPane>
        <igDock:SplitPane x:Name="_imagespace">
            <igDock:ContentPane x:Name="_studypane">
              <StackPanel>
                <ToolBar/>
                <igDock:XamDockManager x:Name="_imagedockmanager">
                  <igDock:XamDockManager.Panes>
                    <igDock:SplitPane x:Name="_imagesplitpane">
                      <igDock:ContentPane x:Name="_thumbnails">
                        <Image/>
                      </igDock:ContentPane>
                      <igDock:ContentPane x:Name="_quadpane">
                        <Image/>
                      </igDock:ContentPane>
                    </igDock:SplitPane>
                  </igDock:XamDockManager.Panes>
                </igDock:XamDockManager>
              </StackPanel>
            </igDock:ContentPane>
        </igDock:SplitPane>
      </igDock:XamDockManager.Panes>
    </igDock:XamDockManager>
  </grid>
</window>

The _studypane contains a toolbar and a splitpane (_imagesplitpane). I don't want the toolbar in a contentpane and I need the _thumbnails and _quadpane to be dockable within the _studypane.  I couldn't figure out how to define the _thumbnails and _quadpane panes without putting them into their own XamDockManger which seems to work but I wasn't sure if it was legal.

Thanks in advance.