sortabla datatable with commandlink problem

[btl_ayd]

Hi.My problem is about commanlink in datatable.I want to get row information when I click commanlink in datatable.Everything works fine until I click sorttable icon for sorting column.After sorting column I cilcked commanlink I get last value of datatable.What is problem ?
here is my datatable tag:

<h:form>
 <rich:dataTable id="tablo" value="#{De.tablo}" var="satir" width="100%" onRowMouseOver="this.style.backgroundColor='#FBF7E6'" onRowMouseOut="this.style.backgroundColor=''" >

 <rich:column sortBy="#{satir.ad}">
 <f:facet name="header"><h:outputText value="Kod" /></f:facet>
 <h:commandLink action="#{De.bak1}" styleClass="comlink" >
 <h:outputText value="#{satir.ad}" styleClass="cell" ></h:outputText>
 </h:commandLink>
 </rich:column>
 <rich:column sortBy="#{satir.ad}">
 <f:facet name="header"><h:outputText value="Kod" /></f:facet>
 <h:commandLink action="#{De.bak1}" styleClass="comlink" >
 <h:outputText value="#{satir.soyad}" styleClass="cell" ></h:outputText>
 </h:commandLink>
 </rich:column>
 </rich:dataTable>

 </h:form>

here is my De managed bean code for load datatable

 public DataModel getTablo(){
 liste =new ArrayList();
 tablo=new ListDataModel();
 Kol k=new Kol("1","a","1a");
 liste.add(k);
 k=new Kol("4","d","4d");
 liste.add(k);
 k=new Kol("9","g","9g");
 liste.add(k);
 k=new Kol("11","r","11r");
 liste.add(k);
 k=new Kol("3","f","3f");
 liste.add(k);
 k=new Kol("90","t","90t");
 liste.add(k);
 k=new Kol("5","i","5i");
 liste.add(k);


 tablo.setWrappedData(liste);
 return tablo;

 }

here is my De managed bean code for getting row value that clicked by user:

 public String bak1(){
 Kol k=(Kol)this.tablo.getRowData();
 System.out.println(k.getAd());
 System.out.println(k.getSoyad());
 System.out.println(k.getKey());
 return "h";
 }

Can anybody help me?