Nested grid with rowExpander creating issues - extjs

Question

I am using Extjs3.2 nested grid with rowExpander.
In my case everything working fine..
but whenever i click on nth row in child grid the parent grid's nth row is also getting selected.
How to Stop this...Please Help??
My Code
var expander = new Ext.ux.grid.RowExpander({
expandOnDblClick : false,
tpl : new Ext.Template('<div id="NestedGridRow-{id}"></div>'),
renderer: function(v, p, record) {
if (record.get('cmaStatus') == 'G') {
p.cellAttr = 'rowspan="2"';
return '<div class="x-grid3-row-expander"></div>';
}
},
});
expander.on('expand', expandedRow);
function expandedRow(obj, record, body, rowIndex){
//absId parameter for the http request to get the absence details.
//Use Id to give each grid a unique identifier. The Id is used in the row expander tpl.
//and in the grid.render("ID") method.
var row = "NestedGridRow-" + record.get("id");
var id2 = "mygrid-" +record.get("id");
sapid_para = record.get('sapid');
//Create the nested grid.
var gridX = new Ext.grid.GridPanel({
id:'nestedGrid',
store: storenested,
//stripeRows: true,
columns: [
{
header : "CMA Date",
width : 120,
sortable : true,
dataIndex : 'cmaDate',
},
{
header : "Source Model",
width : 120,
sortable : true,
dataIndex : 'sourceModel',
},
{
header : "Remarks",
width : 390,
sortable : true,
dataIndex : 'remarks',
}],
height: 120,
id: id2,
plugins : [editor],
renderTo: row,
stripeRows:true,
listeners: {
render: function(gridX) {
gridX.getView().el.select('.x-grid3-header').setStyle('display', 'none');
},
rowclick : function(grid,rowIndex,e) {
alert(rowIndex);
}
},
});
gridX.render(row);
//Ext.getCmp('grid_lineage').getStore().load({params:{start:0, limit:10}});
storenested.load({params:{start:0, limit:10}});

Answer 1

Do you have the same instance of rowSelectionModel on both grids?
EDIT:
Try to add to both of grids definition:
selModel: new Ext.grid.RowSelectionModel({singeSelect:true}),