rowId error

Suite and Optimus Suite 5
#1

When using this code

grid.attachEvent("onBeforeContextMenu", function(rId,cId) { 
    grid.selectRow(rId);
});

i noticed that rId is always 1+, means i have to correct it this way:

    grid.selectRow(rId - 1);

Is this a bug or my vault?

#2

selectRow - selects row by the index, just use the selectRowById command