Serialization Error on Google APP Engine when using Grid

We have a project using a simple view with a Grid in it. deployed on GAE
This grid is initialized with the following code :

public GridView() {
Grid grid = new Grid();

    // Define some columns
    grid.addColumn("Job", String.class);
    grid.addColumn("Name", String.class);
    grid.addColumn("Level", Integer.class);
    grid.addColumn("Nation", String.class);
    grid.addColumn("Noob ?", Boolean.class);
    grid.setEditorSaveCaption("Save my data, please!");
    // Add some data rows
    for (int i = 0; i < 10; i++) {
    grid.addRow("WHM", "Ex", 181, "Twins aders", false);
    grid.addRow("DRK", "Kissi", 200, "Flames", false);
    grid.addRow("INV", "Kira", 195, "Twins aders", true);
    grid.addRow("BLM", "Little", 192, "Twins aders", true);
    grid.addRow("BRD", "Gad", 193, "Twins aders", false);
    grid.addRow("PLD", "Tata", 189, "Flames", true);
    grid.addRow("MNK", "Bremus", 187, "Maelstrom", false);
    grid.addRow("DRG", "Nyra", 190, "Twins aders", false);


[/code]But as soon as the constructor is called we get :

com.vaadin.server.GAEVaadinServlet service: Not serializable!$3 at

Which seems to mean that the RpcDataProviderExtension is not Serializable …?

Any idea to fix this problem ?

No idea ? :frowning:

Yep it seems it was a google problem… the error disappeared without changing anything…

The problem is not google related. It appears when you hat a not attached grid in the session. see:!/thread/12675439

Ok ! thanks