Shell crops Strings with UTF-8 charaters

when I try to print some UTF-8 characters in the shell the end of the line is cropped. E.g.

shell.print("\u2501 Hello World"); 

results in

━ Hello Wor

Looks like the org.jboss.forge.shell.buffers.JLineScreenBuffer is calculating the BufferSize wrong:

public synchronized void write(String s) {
      if (bufferSize + s.length() >= maxBufferSize)
      {
         flushBuffer();
         write(s);
      }

      buffer.put(s.getBytes());
      bufferSize += s.length();
      _flush();
}

s.length() is returning the size of the used Characters, not the Size of the used Bytes. Could be replaced by s.getBytes("UTF-8").length or e.g. this calculation method