I don't think so.

The auth mechanism changed to a new one called WAUTH-1 and we'd have to hack that, that's a lot of work (it took us what? like 2 years the first time?).

Also I think there's an encryption method for every PDU after the user is logged in. Whatsapp wasn't encrypted before (even though it look like it, it just used a dictionary but it wasn't encrypted). The write() function to writes the bytes directly to the network has been overridden with a new one that looks like it encrypts just before writing.

By the way this has been going on since ages the thing is that they still allowed the old login method to give people enough time to upgrade their clients. They finally blocked the old method last weekend.