persisting collection in a custom datagrid

[john_teague]

I appologize for the cross-posting, but I received no responses from
the building controls group.

I have a custom control that inherits from a DataGrid control. I have
a property that has an arraylist of strings. I want to add items as a
child tag of the grid. How is the best way to do this. Here is what I
have as of now.
[ToolboxData("<{0}:OrdersDataGrid runat=server></{0}:OrdersDataGrid>"),

ParseChildren(true)]
public class OrdersDataGrid : System.Web.UI.WebControls.DataGrid
{
...
private ArrayList dataMethodParameter = null;
[Category("Data"),
Editor("System.Windows.Forms.Design.StringCollecti onEditor,
System.Design", "System.Drawing.Design.UITypeEditor, System.Drawing"),
DesignerSerializationVisibility(DesignerSerializat ionVisibility.Content),

PersistenceMode(PersistenceMode.InnerProperty),
Description("Parameter to Pass to the selected OrdersProvider
Method")]
public ArrayList DataMethodParameter
{
get{return this.dataMethodParameter;}
set{this.dataMethodParameter = value;}
}
...

}
What I would like to happen is when items are added via the
StringCollectionEditor they are child items of the control
<cc1:OrdersDataGrid ... >
<DataMethodParameters>
<param>xxx</param>
<param>xxx</param>
...
</DataMethodParamters>