Allow Zero length

Hi,
I am adding  textfield in table in backend using:
If FieldExistsInTable("Forare", "fokId3") = False Then
      Set tdfUpdate = dbsUpdate.TableDefs("Forare")
      With tdfUpdate
      Set tdfField = .CreateField("fokid3", dbText, 16)
                      .Fields.Append tdfField
            tdfField.Properties.Append tdfField.CreateProperty("Format", dbText, "")
            tdfField.Properties.Append tdfField.CreateProperty("Description", dbText, "autoskapat fält")
        End With
    End If
But it does not allow zero length.
What do I need to add to make in allowing zero length?