what you want seems to be internationalization support, which is not the same like UTF-8 support. niether is likely gonna happen anything soon (or ever) though, sorry. even if you would volunteer to do it... we could most likely not accept it, cause for this, you need to change 1 out of 10 lines in the source code, which means that all branches are basically unusable after this, if they have a reasonable ammount of changes.
so.. the basic, technical work is not too complicated, but it would cause a lot of workflow problems, and it is very boring work.
that is my view, at least.
UTF-8 alone allows chat in Chinese. They aren't retarded, they are taught the roman alphabet in school, they can read unit names and defer unit behavior through experience, but lack of UTF-8 support means if they are playing together they can't actually chat to eachother in game (or in lobby likewise)
It isn't THAT bad is it? How much spring code is legitimately dependent on the ASCII standard? Just the chat level data transfer code needs to be modified, not the entirety of the coded system. I mean, I'm not gonna do it, but is it really that hopeless?
 after reading through the rest of the thread, I'd encourage the developers here to stop debating full universal text relations or the ability to customize translations for mods, that should be considered a long term goal. If lobby can support UTF-8 for chat and game names, and in-game can support UTF-8 for chat, that would be fully sufficient for every international player to participate with their local brethren. No one in the world right now is not taught the romanic alphabet. They can read unit names, they can distinguish between building a flash and building a raider. The issue is they can't actually talk to each other in a meaningful way. That could be fixed souly by allowing Chinese/Arabic keyboards to actually input their native characters into the systems.
Those systems are remarkably adaptable. The internet, after all, is fundamentally american. Eastern software is specifically designed to Jerry rig into systems with the least possible effort on the part of the western designed software.