rinetd: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/sbin/rinetd - from package: rinetd

You may install the required package with command apt-get install {package}

Error in other languages:
rinetd: bevel nie gevind nie
rinetd: comandă negăsită
rinetd: comando não encontrado
rinetd: commande introuvable
rinetd: command not found
rinetd: käsku ei ole
rinetd: không tìm thấy lệnh
rinetd: komanda nerasta
rinetd: Kommando nicht gefunden.
rinetd: kommandot finns inte
rinetd: komut yok
rinetd: nie znaleziono polecenia
rinetd: níor aimsíodh an t-ordú
rinetd: no se encontró la orden
rinetd: no s'ha trobat l'ordre
rinetd: opdracht niet gevonden
rinetd: parancs nem található
rinetd: perintah tidak ditemukan
rinetd: príkaz nenájdený
rinetd: příkaz nenalezen
rinetd: команда не найдена
rinetd: командата не е открита
rinetd: 命令找不到
rinetd: コマンドが見つかりません