kermit-sshsub: 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/bin/kermit-sshsub - from package: ckermit

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

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