In fact, I don't know why this limitation exists: (still in 1.2.5)

At client:

net.minecraft.src.ChatAllowedCharacters defined allowed chars.(1)

net.minecraft.src.GuiEditSign allow only allowed characters.(2)

net.minecraft.src.GuiScreen.handleKeyboardInput handle only 1 input character.(3)

At server:

net.minecraft.src.NetServerHandler handleChat forces only allowed chars in chatting.(4) handleUpdateSign replaces all not-allowed chars.(5)

Is it because some character are used for controlling somewhere? Someone made changes and removed these 5 limitations, and it works well so far. (for point3, added processing code)

I usually use Chinese, and Java supports UTF8 by default, so I want to remove these limitation beside using forge. At client side, no file confliction. However, at server side, mm.class (NetServerHandler.java) collide.

I compiled a proper NetServerHandler for my friends this time to include both chinese_support_mod and forge. Is it possible that these limitation be removed directly while injection forge?

What does chinese_support_mod do:

(1) added definition of gbk characters

(2) allow also gbk defined before

(3) if (c > 128 && org.lwjgl.Sys.getVersion().compareTo("2.8.0") < 0){Keyboard.next();char c2 = Keyboard.getEventCharacter();c = (new String(new byte[] {(byte)c, (byte)c2}, java.nio.charset.Charset.defaultCharset().toString().toLowerCase())).toCharArray()[0];}

(4) removed such code

(5) removed such code

Is it possible just remove this whole 'AllowedCharacters' thing?

Hello. If these changes are hard to perform, can someone give me some hints?

I have not looked myself, but first I would recommend looking at the image that contains MC's fonts, see if it supports what you need, if it does not then you might need to generate one and have your signs use it instead.