mudpy handles input, output and formatting of UTF-8 encoded, multi-byte and wide characters, when coupled with a supporting client. By default, however, only printable single-byte ASCII characters are accepted or displayed unless the client negotiates IETF RFC 856 binary mode first. If mudpy needs to send text containing extended characters to a non-binary (7-bit) client, it will first replace those characters with a question mark (?).

For example, the following is the recommended .telnetrc file for interacting with mudpy in binary mode with the Netkit and Inetutils Telnet clients: set binary unset echo unset escape unset flushoutput unset interrupt unset quit unset eof unset localchars