merge more than one field?

[jaimi]

I want to merge several fields within a row, not only the id-field (first).
this is my grid:

I choose OLT31A004T_KEY as id-field, the one witch is merged. But I want to include 'OLT30A001T_KEY_S too.
How to? THX,  Jaimi

  $('#edgZuchtperiode').edatagrid({
   title : 'Zucht-Periode'
  ,iconCls:'icon-pferd'
  ,width:'100%'
  ,height:'auto'
  ,collapsible:'true'
  ,columns:[[ 
    {field:'OLT31A004T_KEY',title:'ZuchtPeriodeKey',width:080,sortable:'true'/*,hidden:'true'*/}
   //,{field :'OLT30A001T_KEY_S',title:'StuteKey',width:080,sortable:'true'/*,hidden:'true'*/}
   ,{field :'OLT30A001T_KEY_H',title:'HengstKey',width:080,sortable:'true'/*,hidden:'true'*/}
   //,{field :'OLT30A001T_KEY_F',title:'FohlenKey',width:080,sortable:'true'/*,hidden:'true'*/}
   //,{field :'ZUP_UELN_F',title:'FohlenUELN',width:240,sortable:'true'}
   //,{field :'ZUP_BEG',title:'Beginn',width:130,sortable:'true'}
   //,{field :'ZUP_END',title:'Ende',width:200,sortable:'true'/*,hidden:'true'*/}
   //,{field :'ZUP_ANZ_BED',title:'Anzahl',width:200,sortable:'true'}
   ,{field :'BED_DAT',title:'Datum',width:80,sortable:'true'}
   ,{field :'ZUV_DES',title:'Beschreibung',width:100,sortable:'true'}
   ,{field :'CBE_GER',title:'CBE_GER',width:100,sortable:'true'}
  ]] ,//columns
  toolbar     : '#tobZuchtperiode',
  url         : 'zuchtperiode.act.php?frm=frmZUP&act=T&prk=' + vPRK,
  remoteSort  : 'true',
  idField     : 'OLT31A004T_KEY',
  queryParams : {sort: 'ZUP_BEG', order: 'DESC'},
  //rownumbers  : 'false',
  singleSelect: 'true',
  pagination  : 'true',
  pageSize    : 30,
  pageList    : [20,30,40,50],
  pagePosition: 'top',
  destroyMsg  : {
   norecord:{title:'Hinweis',
               msg:  'Es wurde kein Satz ausgewählt.'
             },
    confirm :{title:'Bestätigung',
               msg:  'Klicken Sie Ok, um die Zuchtperiode zu löschen.'
             }
  }//destroyMsg
  ,onLoadSuccess:function(data){
   merges = new Array();
    var rowsLength = data.rows.length;
   
    if (rowsLength > 0){
     var curRow, firstRow = data.rows[0], vZUP, counter = 0;
     for (var rowIndex = 0; rowIndex <= rowsLength; rowIndex++){
     if (rowIndex < rowsLength) {curRow = data.rows[rowIndex];}
       if (rowIndex == rowsLength || curRow.OLT31A004T_KEY != vZUP){
       merges[merges.length] = {"id":vZUP, "index":rowIndex-counter, "rowspan":counter};
         firstRow = curRow;
       counter = 1;
      } else {counter++;}//if
      vZUP = curRow.OLT31A004T_KEY;
    }//for
    }//if   

    for(var i=0; i<merges.length; i++)
     $('#edgZuchtperiode').datagrid('mergeCells',{
      field:'OLT31A004T_KEY',
      index: merges.index,
     rowspan:merges.rowspan
    });    
   
    $.messager.show({
      title:'Info'
    ,width:300
     ,height:100
     ,timeout:5000
     ,msg: data.total + ' Zuchtperioden wurden geladen'
    });
   }
 });//edatagrid