jQuery Grid Plugin - jqGrid

Hi,

I have a clientside grid with sortable columns typically:

    colModel: [{
            name: 'ExposureKey',
            index: 'ExposureKey',
            width: 425,
            editable: false,
            align: 'left',
            sortable: true,
            sorttype: 'text'
        }

Other options on the grid:

datatype: "local",

editurl:'dummy.htm',
caption: "",
scrollOffset: 0,

altRows: true,
altclass: "gridstyle",
 loadonce: true

After I load data into the grid and click on a sortable column header, I lose a whole bunch of rows. For example I might load the grid with 120 rows. When I then click the sort, it sorts and removes 80 rows for me !!!

I would appreciate any help from someone who knows why this is happening. I've already searched around but can't find any answers.

Thanks in advance...

peetj....