The "mesh upload" beta of the Second Life client now has depth of field options. The ever-diligent KirstenLee Cinquetti has put that code into the latest version of her SL client. I have yet to learn to control it, but clearly it is there, as you can see in this photo:
(You'll want to look at it full size to see the effect; shrinking a photo hides blur.)
Thanks to KirstenLee Cinquetti, and to the SL staff responsible for this feature; it's yet another option for creative expression in Second Life photography.
P.S. See the Second Life Wiki for details and knobs to twist.