jQuery Grid Plugin - jqGrid

I have a jqGrid for which I have defined a double-click event - code is as follows:

            ondblClickRow: function (rowid) {
                var id = $("#GridQuery").jqGrid("getCell", rowid, "ID");
                $("#ID").val(id);
                $("#FormMain").submit();
                return true;
            },
 

The logic processes the event correctly, but the form submission is ignored and nothing happens. 

How can I get the submit to work?