I have a GH2 and I just bought the Sigma 50mm 1.4 lens for Olympus 4/3 cameras. Do i need an adapter for this to work on my GH2?

Here is the link
Sigma Normal 50mm f/1.4 EX DG HSM Autofocus Lens f/ 310-107 B&H

Yes, you need the adapter also sold at b&h, the Panasonic DMW-MA1. You might have to look around for it, if they are out of it. Video Direct carries it also.

Thanks Jeff!

I just ordered this adapter from B&H...I assume it will work?

Olympus OLMMF2
MMF-2 Four Thirds to Micro Four Thirds Lens Adapter

It costs more than the Panasonic.