s3cl: 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/s3cl - from package: libnet-amazon-s3-perl

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

Error in other languages:
s3cl: bevel nie gevind nie
s3cl: comandă negăsită
s3cl: comando não encontrado
s3cl: commande introuvable
s3cl: command not found
s3cl: käsku ei ole
s3cl: không tìm thấy lệnh
s3cl: komanda nerasta
s3cl: Kommando nicht gefunden.
s3cl: kommandot finns inte
s3cl: komut yok
s3cl: nie znaleziono polecenia
s3cl: níor aimsíodh an t-ordú
s3cl: no se encontró la orden
s3cl: no s'ha trobat l'ordre
s3cl: opdracht niet gevonden
s3cl: parancs nem található
s3cl: perintah tidak ditemukan
s3cl: príkaz nenájdený
s3cl: příkaz nenalezen
s3cl: команда не найдена
s3cl: командата не е открита
s3cl: 命令找不到
s3cl: コマンドが見つかりません