How to Run Minecraft Forge on Ubuntu Client and Server

What I'm using as a client

• Ubuntu 12.04 (Precise)
• Minecraft Client 1.3.2
• Minecraft Forge 4.2.5.303 (Link here)

Client steps

1. Create a backup copy of the installed copy of ~/.minecraft/bin/minecraft.jar
2. Create a temporary directory "mc"
3. Copy your installed copy of minecraft at ~/.minecraft/bin/minecraft.jar to mc
4. cd inside mc, then run jar -xf minecraft.jar
5. rm minecraft.jar
6. nautilus ..
7. Open the minecraft forge file 
8. Extract all the minecraft forge files into mc, they will overwrite files
9. Run jar -cf minecraft.jar .
10. nautilus .
11. Open minecraft.jar and delete META-INF/ now
12. mv minecraft.jar ~/minecraft/bin/minecraft.jar
13. Start minecraft from your minecraft loader (confusingly also named minecraft.jar)
14. If you receive a pop-up saying something like, "FML needs to setup your environment," then all is well.
15. Put mods into the generated ~/.minecraft/mods directory.

Server steps

1. Create a backup copy of the installed minecraft_server.jar
2. Copy the minecraft_server.jar locally into a temporary directory "mc"
3. Make sure its empty from the client jar.
4.  jar -xf minecraft_server.jar
5. rm minecraft_server.jar
6. nautilus ..
7. Open the minecraft forge file
8. Extract all the minecraft forge files into mc, they will overwrite files
9. Now, you will keep the META-INF/manifest
10. jar -cmf META-INF/MANIFEST.MF minecraft_server.jar
11. Put the minecraft_server.jar back onto your server and copy it over your installed minecraft_server.jar. It's a good idea to do a cksum on your local computer and on the server to make sure nothing was lost in transfer.
12. You should be able to run your server as normal. Run it once, then put your mods in the generated mods/ directory.