On the following example, Grid's getSelectionMemory is defined only when when Grid's EnableLocking (line 30) is set to false.

Any ideas to overcome the issue?

Thanks in advance.

<script runat="server">
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!X.IsAjaxRequest)
        {
            this.Store1.DataSource = this.Data;
            this.Store1.DataBind();
        }
    }

    private object[] Data
    {
        get
        {
            return new object[]
            {
                new object[] { "Raphael", 10},
                new object[] { "Batista", 20},
                new object[] { "Saldanha", 30},
            };
        }
    }
</script>
<!DOCTYPE html>
<html>
<head runat="server">
</head>
<body>
    <ext:ResourceManager runat="server" />
    <ext:GridPanel ID="_grd" EnableLocking="false" Title="Sample" Width="640" Height="400" runat="server">
        <Listeners>
            <AfterRender Handler="alert(App._grd.getSelectionMemory);" />
        </Listeners>
        <Store>
            <ext:Store ID="Store1" runat="server">
                <Model>
                    <ext:Model runat="server">
                        <Fields>
                            <ext:ModelField Name="company" />
                            <ext:ModelField Name="price" Type="Float" />
                        </Fields>
                    </ext:Model>
                </Model>
            </ext:Store>
        </Store>
        <ColumnModel runat="server">
            <Columns>
                <ext:Column Text="Company" DataIndex="company" runat="server" />
                <ext:Column Text="Price" DataIndex="price" Width="75" runat="server" />
            </Columns>
        </ColumnModel>
    </ext:GridPanel>
</body>
</html>