Oh.. Scratch that.. It won't even connect anymore now.
Ок, try this (attachment/x86).
// WhatsApp Samsung Galaxy S3
#define ACCOUNT_RESOURCE "iPhone"
Looks like the server now blocks any invalid resource, so this gave me an opportunity to test various resources. I have figured out that the connection works with "S40", "Android" and "iPhone". Since the first two receive encrypted messages for sure, I suggest to try an "iPhone" now. If my theory was right, you will receive not-encrypted messages from all contacts. If not - you will receive unencrypted messages from those with who you used to chat recently, but you won't receive messages from new contacts, or won't receive them at all. Need to test.
And "iOS-2.12.12" was totally incorrect resource. We are lucky it used to work at all and we are still not banned