Set a different character encoding. Leave blank for the default (ISO-8859-1)
At least one Chinese server is known to like "GB2312"
From the commons-net javadoc:
Sets the character encoding used by the FTP control connection.
Some FTP servers require that commands be issued in a non-ASCII
encoding like UTF-8 so that filenames with multi-byte character
representations (e.g, Big 8) can be specified.