Silencing the EP2?

No way at all. It's not an optional, computer generated sound. That sound is the physical shutter closing. If you want a silent camera, you'll need to go get a point and shoot as they tend to use electric shutters (thin film that goes black when charged with a current).

 

It would be interesting to see someone implement something like Leica's "discreet mode" on the shutter, just to help keep the system quiet for those occasional shots where you really want to be discreet.

 

Buy an ever-ready case for it, use the EVF, and pad the LCD. The half case will dampen some of the sound.