Caller ID names are currently 8 bit characters, propably ISO8859-1, depending on what your channel drivers handle.

IAX2 and SIP caller ID names are UTF8 On ISDN Caller ID names are 7 bit, Almost ASCII (See http://www.zytrax.com/tech/ia5.html )

Note: Asterisk does not currently support SIP utf8 caller ID names or caller ID's.

See also