If you use Custom Formatter    then you get formatted value. You need Unformatting to retrive value

Unformatting

As mentioned in Predefined Formatter chapter all predefined types are compatible with the editing modules. This means that the numbers, links, e-mails, etc., are converted so that they can be edited correctly. Also the methods (like getRowData and getCell) that get data, used this unformat in order to get the original value. The question is: What to do if we use a custom formatter function and want to to have the original value back if we use editing or methods getRowData and getCell?

The answer is: You can use your own custom unformatter function to do that. This function can be used in colModel

<script>
jQuery("#grid_id").jqGrid({
...
   colModel: [ 
      ... 
      {name:'price', index:'price', width:60, align:"center", editable: true, unformat:myunformatfunc},
      ...
   ]
...
});
function myunformatfunc ( cellvalue, options, cellobject)
{
   // do something here
   return unformated_value;
} 
</script>

http://www.trirand.com/jqgridwiki/doku.php?id=wiki:custom_formatter

it doesnt returns the DATA you've provided for this row (using setRowData for example), bu instead ti returns only formatted values of visible columns.

and as I see in code - the original data itself doesn't even stored, so there isn't any way to retrieve original data you've added to grid? this is stupid.