s3acl: 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/bin/s3acl - from package: libnet-amazon-s3-tools-perl

You may install the required package with command apt-get install {package}
Error in other languages:
s3acl: bevel nie gevind nie
s3acl: comandă negăsită
s3acl: comando não encontrado
s3acl: commande introuvable
s3acl: command not found
s3acl: käsku ei ole
s3acl: không tìm thấy lệnh
s3acl: komanda nerasta
s3acl: Kommando nicht gefunden.
s3acl: kommandot finns inte
s3acl: komut yok
s3acl: nie znaleziono polecenia
s3acl: níor aimsíodh an t-ordú
s3acl: no se encontró la orden
s3acl: no s'ha trobat l'ordre
s3acl: opdracht niet gevonden
s3acl: parancs nem található
s3acl: perintah tidak ditemukan
s3acl: príkaz nenájdený
s3acl: příkaz nenalezen
s3acl: команда не найдена
s3acl: командата не е открита
s3acl: 命令找不到
s3acl: コマンドが見つかりません