camlp5r: 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/camlp5r - from package: camlp5

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

Error in other languages:
camlp5r: bevel nie gevind nie
camlp5r: comandă negăsită
camlp5r: comando não encontrado
camlp5r: commande introuvable
camlp5r: command not found
camlp5r: käsku ei ole
camlp5r: không tìm thấy lệnh
camlp5r: komanda nerasta
camlp5r: Kommando nicht gefunden.
camlp5r: kommandot finns inte
camlp5r: komut yok
camlp5r: nie znaleziono polecenia
camlp5r: níor aimsíodh an t-ordú
camlp5r: no se encontró la orden
camlp5r: no s'ha trobat l'ordre
camlp5r: opdracht niet gevonden
camlp5r: parancs nem található
camlp5r: perintah tidak ditemukan
camlp5r: príkaz nenájdený
camlp5r: příkaz nenalezen
camlp5r: команда не найдена
camlp5r: командата не е открита
camlp5r: 命令找不到
camlp5r: コマンドが見つかりません