mlv-smile: 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/mlv-smile - from package: mlv-smile

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

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