Need some help please

I am using a multiselect jqgrid with onSelectRow, onSelectAll and gridComplete event. My issue is when i check selectall check box which is selecting all the rows in the grid view but as soon as the gridComplete is called selectall check box is getting unchecked and i am not able to unselect all the rows.

Please let me know if some thing i need to take care here. below is my code

$("#"+tableID).jqGrid({

datastr: wellboresData,

datatype:"jsonstring",

colNames:['id','Well Legal Name','Wellbore Legal Name', 'Region', 'Country','State','Kick-off Latitude','Kick-off Longitude','Bottom Hole Latitude','Bottom Hole Longitude'],

colModel:[

{name:'id', width:100,hidden: true, align:"left", key:true},

{name:'wellLegalName', width:"15%", align:"left"},

{name:'wellboreLegalName', width:"10%", align:"left"},

{name:'region', width:"15%", align:"left",sortable:true, jsonmap: "location.region"},

{name:'country', width:"15%", align:"left",sortable:true, jsonmap: "location.country"},

{name:'state', width:"10%", align:"left",sortable:true, jsonmap: "location.state"},

{name:'kolat', width:"10%", align:"right",sortable:true, sorttype:"float", jsonmap: "location.koCoord.latitude"},

{name:'kolong', width:"10%", align:"right",sortable:true, sorttype:"float", jsonmap: "location.koCoord.longitude"},

{name:'bhlat', width:"10%", align:"right",sortable:true, sorttype:"float", jsonmap: "location.bhCoord.latitude"},

{name:'bhlong', width:"10%", align:"right",sortable:true, sorttype:"float", jsonmap: "location.bhCoord.longitude"}

],

rowNum:20,

rowList:[5,10,20,50,100,200,500],

pager: '#'+pagerID,

sortname: 'id',

sortorder: "desc",

multiselect: true,

caption: "Wellbore List",

width:width,

height:"100%",

shrinkToFit:true,

jsonReader:{

repeatitems:false,

id:"Id",

root: function(wellboresData){return wellboresData;},

page: function(wellboresData){return 1;},

total: function(wellboresData){return 1;},

records: function(wellboresData){return wellboresData.length;}

},

onSelectRow: function(rowid,status){

if(status){

if (gridwellboreContext != null) {

if($.inArray(rowid,gridwellboreContext) === -1){

gridwellboreContext.push(rowid);

}

} else{

gridwellboreContext.push(rowid);

}

}else{

if($.inArray(rowid,gridwellboreContext) > -1){

gridwellboreContext.splice($.inArray(rowid,gridwellboreContext),1);

}

}

$("#"+tableID).data("modified", true);

},

onSelectAll: function(aRowids,status){

if(status){

for(var i=0; i<aRowids.length; i++){

if (gridwellboreContext != null) {

if($.inArray(aRowids[i],gridwellboreContext) === -1){

gridwellboreContext.push(aRowids[i]);

}

} else{

gridwellboreContext.push(aRowids[i]);

}

}

}else{

for(var i=0; i<aRowids.length; i++){

if($.inArray(aRowids[i],gridwellboreContext) > -1){

gridwellboreContext.splice($.inArray(aRowids[i],gridwellboreContext),1);

}

}

}

$("#"+tableID).data("modified", true);

},

gridComplete: function(){

if (gridwellboreContext != null) {

$.each(gridwellboreContext, function (e, wellboreId) {

$("#"+tableID).jqGrid('setSelection',wellboreId);

});

}

}

});

$("#"+tableID).jqGrid('navGrid','#'+pagerID,

{edit:false,add:false,del:false},

{},

{},

{},

{multipleSearch:true, multipleGroup:true}

);