CellTracker dye in necrotic cells? - (Jun/21/2011 )

I'm using Celltracker green reagent from Invitrogen to stain my cells for flow cytometry. I know that this reagent is colorless, crosses cell membranes and inside cells react with thiols in the cytosol and then becomes a fluorescent dye.
However, in my experiments, after I stain the cells, I make them apoptotic. So my question is what happens to the dye when cells become apoptotic and necrotic? In early apoptotic cells I guess the dye stays inside for as long as the membrane is intact, but in necrotic cells? Do they start to leak and can the dye then leak out and react with other cells I have in my tube? I need to know that I only stain this specific cell type and not cells that I add at a later stage.
Thanks for your help!

I would email the tech support crew at Invitrogen, they should be able to give you product specific advice.