listShuffle problem

[mootje]

i'm having a probleme with listShuffle

  i cant load the SourceValue  , i'm usinng a List of String  here is the code that i'm using

<rich:listShuttle id="myListShuttle"

orderControlsVisible="false"

immediate="true"

fastMoveControlsVisible="false"

fastOrderControlsVisible="false"

sourceValue="#{adduser.examList}"

targetValue="#{adduser.selExamsList}"

sourceRequired="true"

targetRequired="true"

var="items"

sourceCaptionLabel="Examens"

targetCaptionLabel="Examens Selectionne">

</rich:listShuttle>

                                             <rich:listShuttle id="myListShuttle"

orderControlsVisible="false"

immediate="true"

fastMoveControlsVisible="false"

fastOrderControlsVisible="false"

sourceValue="#{adduser.examList}"

targetValue="#{adduser.selExamsList}"

sourceRequired="true"

targetRequired="true"

var="items"

sourceCaptionLabel="Examens"

targetCaptionLabel="Examens Selectionne">

</rich:listShuttle>

and this code contains in the managebean

     private UserService userService;

private ExamService examService;

private List<String> examList;

private List<String> selExamsList;

private List<Exam> exams;

+ getters and setters

//this is done directy after creating instance

@PostConstruct

public void initialize()

{

                 // this gets the data from database works (tested )

this.exams = examService.chargerTout();

               // examList value binded to source value

this.examList = new ArrayList<String>();

               //targetValue empty

this.selExamsList =  new ArrayList<String>();

//adding values to the SourceValue

for (int i = 0; i < this.exams.size(); i++) {

this.examList.add(this.exams.get(i).getExamname());

}

this.message="";

  this.user=new Users();

}

the examList attribut is filled directly after the instance is created so it should be filled and normaly i don't need a converter because i'm using strings

i hope somebody is going to respond quick thanks