I can't rename an item using foreign characters.
In this bug I attached a screenshot with the bug reproduced.
I did only test with Arabic, Korean and Chinese.
Also, I'd like to know if it's possible to be able to use ALT+number commands, so I can use characters such as †, ¿, ®, ™ etc
Environment
Operating System: Windows 7 SP1 64-bit
Java Version: "1.7.0_07"
Java(TM) SE Runtime Environment (build 1.7.0_07-b11)
Java HotSpot(TM) 64-Bit Server VM (build 23.3-b01, mixed mode)
Minecraft Version: 1.4.3 (prerelease) Vanilla (no mods)
LWJGL Version: 2.8.5-nightly (25-oct-2012)
Please, use the search function in the future to look if the bug was posted already.