var comment = new GC.Spread.Sheets.Comments.Comment();
comment.text("new comment!");
comment.backColor("orange");
comment.displayMode(GC.Spread.Sheets.Comments.DisplayMode.alwaysShown);
activeSheet.getCell(5,5).comment(comment);

activeSheet.bind(GC.Spread.Sheets.Events.CommentRemoving, function (e, info) {    
      info.cancel = true;
});
