How to get Copy From combobox selected value

Dear Exprerts,

I would like to get the selected value of the "Copy from" combobox in 8.8 and 8.81 with next code but without luck.

If (pVal.ItemUID = "10000330") Then
            If (pVal.EventType = BoEventTypes.et_COMBO_SELECT) And (pVal.BeforeAction = False) Then
                Dim oDeliveryForm As SAPbouiCOM.Form = SBO_Application.Forms.GetForm(pVal.FormType, pVal.FormTypeCount)
                Dim oComboBox As SAPbouiCOM.ComboBox

                'Dim oEditText As SAPbouiCOM.EditText

                Dim str As String

                'Dim lNum As Long

                oComboBox = oDeliveryForm.Items.Item("10000330").Specific

                str = oComboBox.Selected.Description
                SBO_Application.MessageBox(str)
            End If
        End If

In the 2007A version this is worked. Anybody has idea about what did I wrong?

Thank you in advance.

Nghia