anchor.diff:  
                            <wiki:PageType type="page">
                              <td>
  -                              <% if( currentPage.getVersion() > 1 ) { %>
  -                                   <wiki:DiffLink version="<%=Integer.toString(currentPage.getVersion())%>" 
  -                                                  newVersion="<%=Integer.toString(currentPage.getVersion()-1)%>">
  -                                       from version <%=currentPage.getVersion()-1%> to <%=currentPage.getVersion()%>
  +                              <wiki:CheckVersion mode="notfirst">
  +                                   <wiki:DiffLink version="current" 
  +                                                  newVersion="previous">
  +                                       from version <wiki:PreviousVersion/> to <wiki:PageVersion/>
                                      </wiki:DiffLink>
  -                               <% } %>
  +                              </wiki:CheckVersion>
                              </td>
                            </wiki:PageType>
   
  
positive.code:                          <td>
                               <wiki:PageType type="page">
                               <wiki:DiffLink version="latest" 
                                              newVersion="<%=Integer.toString(currentPage.getVersion())%>">
                                   <wiki:PageDate/>
                               </wiki:DiffLink>
                               </wiki:PageType>
  
negative.code:     </wiki:PageType>
      <wiki:PageType type="attachment">
  
         <form action="<wiki:Variable var="baseurl"/>attach" method="post" enctype="multipart/form-data">
  
             <%-- Do NOT change the order of wikiname and content, otherwise the 
                  servlet won't find its parts. --%>
  