smp_zone_unlock: 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

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/smp_zone_unlock - from package: smp-utils

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