Your character set's control character is another character set's perfectly normal printable character.

As for making the kernel enforce a single character set for the filesystem: No. No. No. Put another way: No.

http://yarchive.net/comp/linux/utf8.html

From Al Viro:

    Bullshit.  It has _nothing_ to characters, wide or not.  For system filenames
    are opaque.  The only things that have special meanings are:
            octet 0x2f ('/') splits the pathname into components
            "." as a component has a special meaning
            ".." as a component has a special meaning.
    That's it.  The rest is never interpreted by the kernel.