$('#pageflipper').pageflipper(); 
      //Contains ul with a li pr page

      $( '#page1' ).focus( function() {
        //focushandler for #page3
        //Here you can do ajax or whatever
      } )

      $( '#page2' ).focus( function() {
        //focushandler for #page3
        //Here you can do ajax or whatever
      } )

      $( '#page3' ).focus( function() {
        //focushandler for #page3 
        //Here you can do ajax or whatever
      } )