v2 set tooltip example?

can somene give me an example of how to set a tooltip for a cell?

For one cell -

obj.setCellTooltip("some text", 1, 1);

or

obj.setCellTooltip(myTooltips2dArray);

Can I modify the tooltip display time?

Alex, can you give a working example? I tried using the codes above with no luck. Basically I need a tooltip for data that overflows the grid since rows will not resize height based on data.

Well. Let me clearify, I get no errors, but how does the tooltip get provoked?

I want the same tooltip for a row, so I use it like this
obj.setCellTooltip(function(i, j){return tooltip[j]});
The problem is when the tooltip is too long, it disappear before someone could read it.