My friend and I set up a server the other day and it works fine without any mods. We have successfully modded our client versions with IC2 1.71, advanced machines, and railcraft. As soon as we try to add Modloader MP server and Minecraft Forge server, our server won't launch. All it says is that minecraft_server.jar is corrupt or invalid. It doesn't give any details other than that.
To install modloader MP and minecraft forge, I open the jar and put in the MP files and then the forge files. I do not delete the meta-inf. I've tried compressing the files and renaming it minecraft_server.jar and I've tried naming the folder mincraft_server.jar, neither of which worked. Does anyone know what the issue might be? Btw, I'm using modloader MP version 1.1 v2.1 and minecraft forge 1.3.3.12. Thanks for any help you can give!