jQuery Grid Plugin - jqGrid

Hi,

I am trying to add a new row to a grid when a button is clicked. When

the button is click the following function is called:

$("#assignPos").click(function() {

$("#list").editGridRow("new",{height:280,reloadAfterSubmit:false});

});

When the button is clicked the overlay appears but the actual modal window remains hidden. I have inspected the page with Firebug and the display style (for modal) is set to block which means it should be showing.

I have modal windows working on another page in the site but I am calling this one in a different way and I can't figure out where I am going wrong!

My grid call is as follows:

$("#list").jqGrid({
                       url:'assets/includes/listPositions.cfm?PersonID=0',
                       datatype: 'json',
                       colNames:['ID','Position Code','Position Type','Parish Name','Start Date','Finish Date','CommitteeMemberTypeID','ClergyStatusID'],
                       colModel:[
                       {name:'tjppid',key: true,index:'tjppid',editable:true,editoptions:{readonly:true},width: 40},
                       {name:'PositionID',index:'PositionID',width:150},
                       {name:'PositionType',index:'PositionType',width: 250},
                       {name:'ParishName',index:'ParishName',width: 260},
                       {name:'StartDate',index:'StartDate',sorttype:"date",editable:true, editoptions:{size:10,maxlength:10},width:100},
                       {name:'FinishDate',index:'FinishDate',sorttype:"date", editable:true, editoptions:{size:10,maxlength:10},width:100},
                       {name:'CommitteeMemberTypeID',index:'CommitteeMemberTypeID', width:0,editable:true,edittype:'select',editoptions:{value:"<cfloop query="qCMType"><cfoutput>#MemberTypeID#:#MemberType#<cfif recordcount gt currentrow>;</cfif></cfoutput></cfloop>"}},
                       {name:'ClergyStatusID',index:'ClergyStatusID',width: 0,editable:true,edittype:'select',editoptions:{value:"<cfloop query="qClergyStatus"><cfoutput>#StatusID#:#Status#<cfif recordcount gt currentrow>;</cfif></cfoutput></cfloop>"}}],
                       sortname: 'PositionType',
                       sortorder: "asc",
                       viewrecords: true,
                       imgpath: 'assets/js/jqGrid/themes/sand/images',
                       jsonReader: {repeatitems: false},
                       height:120,
                       onSelectRow: function(id){
                            if(id && id!==lastsel2){
                                $('#list').restoreRow(lastsel2);
                                $('#list').editRow(id,true,pickdates);
                                lastsel2=id;
                                }
                       },
                       editurl: "assets/includes/assignPosition.cfm"

});

Any suggestions? Maybe there is an easier way to have a button that when clicked opens the modal form for adding a new row. The grid may have 0 or more rows already.

Cheers,

Dave