Cannot invoke method

[[EMAIL PROTECTED]]

Hi,
i have this problem, if you can you look my code, if you look my mxml 
file when press "PassaPOJO" button, flex lunch this error
Error: Cannot invoke method 'Lista'.
Why? what i wrong, please can you help me


java side simple function
public void Lista(PfVO pf)
{
System.out.print(pf.getDe50pf());
}
Devis

class vo.as400.PfVO {


public var aacupf : Number;
public var blrepf : String;
public var cartpf : String;
public var cdogpf : String;
public var ceaqpf : Number;
public var ceulpf : Number;
public var cfpfpf : vo.as400.CCategoriFiscaleVO;
public var civapf : String;
public var cma1pf : String;
public var cma2pf : String;
public var cma3pf : String;
public var cma4pf : String;
public var cma5pf : String;
public var cmp1pf : String;
public var cmp2pf : String;
public var cmp3pf : String;
public var cnaqpf : String;
public var cnvepf : String;
public var coaqpf : Number;
public var coulpf : Number;
public var de50pf : String;
public var dtumpf : Number;
public var fl10pf : String;
public var fl20pf : String;
public var fl30pf : String;
public var fl31pf : String;
public var fl32pf : String;
public var fl33pf : String;
public var fl34pf : String;
public var fl35pf : String;
public var fl36pf : String;
public var fl37pf : String;
public var fl38pf : String;
public var fl39pf : String;
public var fl40pf : String;
public var fl41pf : String;
public var fl42pf : String;
public var fl43pf : String;
public var fl44pf : String;
public var fl45pf : String;
public var fl46pf : String;
public var fl47pf : String;
public var fl48pf : String;
public var fl49pf : String;
public var fla1pf : String;
public var fla2pf : String;
public var fla3pf : String;
public var fla4pf : String;
public var fla5pf : String;
public var fla6pf : String;
public var fla7pf : String;
public var fla8pf : String;
public var flicpf : String;
public var fptgpf : String;
public var ftcopf : String;
public var ggcupf : Number;
public var linepf : String;
public var ltripf : Number;
public var marcpf : String;
public var mmcupf : Number;
public var modevo : vo.as400.ModeVO;
public var nrazpf : Number;
public var orumpf : Number;
public var peunpf : Number;
public var pfvopk : vo.pk.PfVOPK;
public var qmxbpf : Number;
public var ricopf : String;
public var scmnpf : Number;
public var slinpf : String;
public var socupf : Number;
public var stagione : vo.as400.CStagione;
public var strepf : String;
public var volupf : Number;



public static var regClass = 
Object.registerClass("vo.as400.PfVO",vo.as400.PfVO);

public function PfVO() {

}


}<?xml version="1.0" encoding="utf-8"?>

<mx:Application xmlns:mx="http://www.macromedia.com/2003/mxml";
themeColor="haloSilver"
backgroundColor="#FFFFFF"
xmlns="*">


<!--WorkFlow Campionario Via del Corso S.p.A. -->
<mx:RemoteObject id="Campionario" named="FCampionarioRO"
fault="errorCall(event.fault.description)" showBusyCursor="true">
<mx:method name="Test" result="onResult(event.result)"/>
<mx:method name="Test_AS400" result="onResult(event.result)"/>
<mx:method name="Lista"/>

</mx:RemoteObject>


<mx:Binding source="{PfVO(vopf[0]).stagione.cdc_stag==undefined ?'':PfVO(vopf[0]).stagione.cdc_stag}" destination="cdc_art.text" /> 


<mx:Binding source="{PfVO(vopf[0]).stagione.dsc_stag==undefined ?'':PfVO(vopf[0]).stagione.dsc_stag}" destination="cdc_art2.text" />
<mx:Binding source="{PfVO(vopf[0]).de50pf==undefined ?'':PfVO(vopf[0]).de50pf}" destination="descr.text" />
<mx:Binding source="{PfVO(vopf[0]).pfvopk.matepf==undefined ?'':PfVO(vopf[0]).pfvopk.matepf}" destination="mate.text" />
<mx:Script source="as/labelFunction.as"/>


<mx:Script>

var StartX=0;
var Max_Result=20;
import vo.as400.*;
var vopf:Array;

function AutoInc()
{
if(vopf[0].de50pf==undefined)
{
StartX=0;
Campionario.Test_AS400(StartX,Max_Result); 
} 
else
{
StartX++;
Campionario.Test_AS400(StartX,Max_Result);
} 

}




function updateObj(oEvent:Object,sColumn:String):Void
{
// roModel.currentSeason.editField(0,"de50pf", oEvent.target.text);
vopf.editField(0, "de50pf", oEvent.target.text);
}




function errorCall(alert)
{
mx.controls.Alert.show("Web service failed!"+alert, "Errore Interno ",
mx.controls.Alert.OK);
}


function onResult(result):Void
{

vopf=result;
roModel.currentSeason.dataProvider=result;
}

function Aggiorna(vo:Object):Void
{
Campionario.Lista(vo);
}


</mx:Script>


<mx:Model id="roModel">
<currentSeason>
{vopf}
</currentSeason>

</mx:Model>


<mx:Button label="Product" click="AutoInc();"/>
<mx:Button label="Product" click="vopf=new Array()"/>
<mx:Button label="Te" click="Campionario.Test_AS400(StartX,Max_Result)"/>
<mx:Button label="PassaPOJO" click="Aggiorna(vopf[0])"/>


<mx:TextInput id="descr" focusOut="updateObj(event,'0')"/>
<mx:TextInput id="mate" />
<mx:TextInput id="cdc_art2" />
<mx:TextInput id="cdc_art"/>
<mx:DataGrid dataProvider="{vopf}" width="100%">
<mx:columns>
<mx:Array>
<mx:DataGridColumn columnName="de50pf" headerText="Descrizione"/>
<mx:DataGridColumn labelFunction="getModello" headerText="Materiale"/>
<mx:DataGridColumn labelFunction="getStagione" headerText="Stagione"/>
<mx:DataGridColumn labelFunction="getDsc_stag" headerText="Desc_stag"/>
<mx:DataGridColumn labelFunction="getCategoria" headerText="Categoria"/>
</mx:Array>
</mx:columns>
</mx:DataGrid>
</mx:Application>