makejail: command not found

Have You tried accessing the binary with the full path?

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/makejail - from package: makejail

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