jQuery Grid Plugin - jqGrid

In the jqgrid 4.1.1 source we have:

6830: rp_ge.reloadAfterSubmit = rp_ge.reloadAfterSubmit && $t.p.datatype != "local";

...

6870   if(rp_ge.reloadAfterSubmit) {
6871     $($t).trigger("reloadGrid");

I have tree grid with form editing. the 'datatype' variable gets set to 'local'. Given the code above it is unclear to me how one can set reloadAfterSubmit :true and have the treegrid refresh after a successful form edit update?

        url:'/worksheetxml.sz?parent=13',
        treeGrid: true,
        treeGridModel: 'adjacency',
        mtype: 'POST',
        rowNum: 200,
        treedatatype: 'xml',
        datatype: 'xml',
        ExpandColumn: 'build_type',
        ExpandColClick: true,
        forceFit: true,
        loadui: 'block',
        caption: 'Worksheet',
        viewrecords: true,

        editurl: 'worksheetxml.sz?parent=13,

        .....