jQuery Grid Plugin - jqGrid

Using the next grid:

var lastsel;
Query("#grid0").jqGrid({
    url:url_get,
    datatype: "xml",
    colNames:[jq_cols[0].col_caption,jq_cols[0].col_caption],
    colModel:[
        {name:'espcode',index:'espcode', width:64, key:true, editable:true, align:"right",editoptions: {size:3, maxlength: 3}},
        {name:'espname',index:'espname', width:210,editable:true,editoptions: {size:38, maxlength: 40}}
        ],
    rowNum:jq_numrows,
    autowidth : true,
    shrinkToFit: false,
    scrollOffset: 0,
    gridview: true,
    pager: jQuery('#pager'),
    viewrecords: true,
    onSelectRow: function(id){
        if(id && id!==lastsel){
            jQuery('#grid0').restoreRow(lastsel);
            jQuery('#grid0').editRow(id,true);
            lastsel=id;
        }
    },
    gridComplete: function() {
        lastsel=undefined;
    },
    height:jq_numrows * jq_hr,
    hidegrid: false,
    editurl:url_post,
    caption: jq_grid[0].caption,
    loadui:"block"
});

I use the post id as parameter to select the record data on a server (where id='x').
The problem occurs when the data has been published in the column whose ColModel key:true, it is not updated
the rowid. Subsequent editions keep the id of the last reading, for example:

Data read:
id: C50
espcode: C50
espname: Users

First edit:
Grid -> Post
id: C50 -> C50
espcode: C50 -> U60
espname: Users -> Users

update table SET espcode = 'U60', espname = 'Users' WHERE espcode = 'C50' (ok)

Second edit:
Grid -> Post
id: C50 -> C50
espcode: U60 -> C70
espname: Users -> Users

update table SET espcode = 'C70', espname = 'Users' WHERE espcode = 'C50' (not ok, espcode = 'C50' not exist)

The possible solution I've found is to run jQuery('#grid0').trigger('reloadGrid'), in a function
within the parameter aftersavefunc of editRow function, to reload ID's:

jQuery('#grid0').editRow(id,true,'','','','',jq_reload);

function jq_reload(id, res){
    if (res.statusText != 'OK') alert(jq_serverXHR(res));
    jQuery('#grid0').trigger('reloadGrid');
}

Now with 3.6, I can use serializeRowData to add a value with data of rowid on last edit:

var rowKey;
var lastsel;
Query("#grid0").jqGrid({
    url:url_get,
    datatype: "xml",
    colNames:[jq_cols[0].col_caption,jq_cols[0].col_caption],
    colModel:[
        {name:'espcode',index:'espcode', width:64, key:true, editable:true, align:"right",editoptions: {size:3, maxlength: 3}},
        {name:'espname',index:'espname', width:210,editable:true,editoptions: {size:38, maxlength: 40}}
        ],
    rowNum:jq_numrows,
    autowidth : true,
    shrinkToFit: false,
    scrollOffset: 0,
    gridview: true,
    pager: jQuery('#pager'),
    viewrecords: true,
    serializeRowData:function(postdata) {
        postdata.rowKey = rowKey;
        return postdata;
    },
    onSelectRow: function(id){
        if(id && id!==lastsel){
            jQuery('#grid0').restoreRow(lastsel);
            rowData = jQuery('#grid0').getRowData(id);
            rowKey = rowData.espdate;
            jQuery('#grid0').editRow(id,true);
            lastsel=id;
        }
    },
    gridComplete: function() {
        rowKey = undefined;
            lastsel= undefined;
    },
    height:jq_numrows * jq_hr,
    hidegrid: false,
    editurl:url_post,
    caption: jq_grid[0].caption,
    loadui:"block"
});

The problem:
The edited postdata in serializeRowData, show in grid.

I use a grid with a key column with date formatter:

    colModel:[
        {name:'espdate',index:'espdate', width:64, key:true, editable:true, align:"right",
            formatter:'date', formatoptions:{srcformat:"Y-m-d",newformat:"j M Y"},
                    editoptions: {size:12, dataInit:function(el){$(el).datepicker({dateFormat:'d M yy',minDate: '+1', maxDate: jq_grids['#grid0'].maxDate ,onClose: function(){
                    $(this).focus();},changeMonth: true});}, readonly:'readonly'}},
        {name:'espname',index:'espname', width:210,editable:true,editoptions: {size:38, maxlength: 40}}
        ],

I use the datepicker parse function (in a function) for post date in SQL format:

    serializeRowData:function(postdata) {
        postdata.espdate = ig_sqlDate(postdata.espdate);
        postdata.rowKey = ig_sqlDate(rowKey);
        return postdata;
    },

If i use unformat option in colModel, getRowData retrieve data in srcformat, but inline edit post data in newformat.