I'm just facing another problem, which maybe comes out of my implementation?
When i load a tree node which is closed and loaded: false, the ajax request don't get executed.
I found out it's because of the first time i use datatype: 'local'
And then manually change it to json…
grid.jqGrid('setGridParam', { dataType: 'json' });
grid.jqGrid()[0].addJSONData(data); //Apply the faked “local” data…
It's fine with pagination (second page get's loaded with ajax), but it doesn't work with the tree ajax loading..?