Sadly not. The current PWO client was originally built in the days before Unicode was a standard, and as a result, the client doesn't have awareness of it. As a result, all text sent to and from the client is rendered using your own computer's language settings.
To explain why this is an issue, let me explain a little bit of computer history. Before Unicode, different languages would often implement their own character sets to allow computers to display accented letters, specialist symbols and anything else unique to a particular language or purpose. Computers store messages in a bit format, then use these character sets to map each byte to a letter, number or symbol. The problem happens when software built in one language is used on a system that expects a different language. The two different character sets may share the same bytecodes, but point to two very different letters or symbols, causing confusion.
This, in a nutshell, is what causes PWO's "Stuck at Authenticating" bug. When you try to connect to the PWO Server, PWO does certain checks to make sure the version of the game you're playing is up-to-date, among other things, before it begins to try to log you in. Where the bug comes in is in how these checks work. While I can't go in to the exact mechanics for security reasons, essentially, if your PC is set to use a non-English locale for non-Unicode programs, what the server sends, and what your PC understands, can end up being two very different things. This means PWO gets confused, and thinks it hasn't been told whether it's allowed to continue logging in or not - so, PWO keeps waiting to be told, leading to the freeze because the server won't send the message again.
Unfortunately, fixing this bug is non-trivial. Essentially, it'll require significant redevelopment of the client to make it "Unicode-aware". Thus, for now, changing the locale is the only solution. In truth, PWO would be better served with a complete new client; but unfortunately, that project is not on our roadmap at present, as the manpower and expertise required is more than we can reasonably dedicate right now while continuing to develop the game itself.