Hello Tony!

After the rows of the grid will be grouping the information about the grouping item will be deleted (see lines 169-171 of grid.grouping.js):

grp.sortitems[0] = [];
grp.sortnames[0] = [];
grp.summaryval[0] = [];

I wanted to collapse not all rows in the jqGrid but a selected one. For example I would like on the example http://www.ok-soft-gmbh.com/jqGrid/DisplayLog.htm