jQuery Grid Plugin - jqGrid

Ok, I was forced to switch from a static xml file to a static json file for data.  XML file got way too big - over 28,000 lines long and over 2MB big.  I have reformatted my jqGrid function to handle the parsing of my data.  I noticed that the documentation mentioned the jsonmap (like xmlmap).  But in all the examples, both in documentation and the simulated examples, I can not find any where the jsonmap is being used.  Is it required or still used as a column model option designation??  I know that jqgrid is reading my grid setup because my column names are designated within the colModel and not within the colNames.  But I can not get any data to display within the grid.

Tony

jQuery 1.4.2

jqGrid 3.6.4