In Reply to: How to prohibit some users to ftp or telnet posted by moonriver on September 17, 2003 at 02:51:55:
If you want to block ftp, then use the file /etc/ftpd/ftpusers. Details see "man ftpusers".
If you want to block telnet, then use /var/adm/inetd.sec. If you don't have this file, then create it. See "man inetd.sec" for sample entries.
Good luck.