buthead: 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/buthead - from package: buthead

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