Why doesn't this code produce Actuals lines in the Timesheet Data Set

I use this code to create an administrative line in my timesheet.  The Timesheet line gets added, but no actuals lines are generated (in the Actuals DataTable).  How can I accomplish this?

    private void PrepareTimesheet (Guid tsUID, SvcTimeSheet.TimesheetDataSet ds)
        {
            SvcAdmin.AdminClient adminSvc = new SvcAdmin.AdminClient();
            SvcAdmin.TimesheetLineClassDataSet tslcds = adminSvc.ReadLineClasses(SvcAdmin.LineClassType.AllNonProject, SvcAdmin.LineClassState.Enabled);


            SvcTimeSheet.TimesheetDataSet.LinesRow line = ds.Lines.NewLinesRow();
            line.TS_UID = tsUID;
            line.TS_LINE_UID = Guid.NewGuid();
            line.TS_LINE_CLASS_UID = tslcds.LineClasses[0].TS_LINE_CLASS_UID;
            line.TS_LINE_COMMENT = "Added by code sample.";
            line.TS_LINE_STATUS = (byte)PSLib.TimesheetEnum.LineStatus.NotApplicable;
            line.TS_LINE_VALIDATION_TYPE = (byte)PSLib.TimesheetEnum.ValidationType.Unverified;
            line.TS_LINE_CACHED_ASSIGN_NAME = tslcds.LineClasses[1].TS_LINE_CLASS_DESC;  // this is the vacation task
            ds.Lines.AddLinesRow(line);

            SvcTimeSheet.TimeSheetClient tsc = new SvcTimeSheet.TimeSheetClient();
            tsc.PrepareTimesheetLine(tsUID, ref ds, new Guid[] { line.TS_LINE_UID });

        }