A few of you were wondering how to get 1.6.2 mods on 1.6.4 and connect to 1.6.4 servers. It turns out the client wasn’t actually modified in the update, so you can still use a 1.6.2 client to connect to a 1.6.4 server, IF you change one number in the code. Here are the steps:
1. Download the modified class file from here (go ahead, open it with jd-gui or any other decompiler and read the source if you distrust it):
2. Open the folder %appdata%/.minecraft/versions/<your_modded_folder>/
3. Then when you’re there, open up “<jar-name>.jar” with WinRar, 7-zip, or any other archiver that supports .jar files.
4. Go ahead and drop bcw.class in there, then you’re done!
5. Run Minecraft with your modded profile, and try it out.
In order to connect to a server, you must double click it when it is loading, otherwise the client will prevent you from connecting to it. Example: