mclcm: 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/mclcm - from package: mcl

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

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