mkcamlp5.opt: 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/mkcamlp5.opt - from package: camlp5

You may install the required package with command apt-get install {package}
Error in other languages:
mkcamlp5.opt: bevel nie gevind nie
mkcamlp5.opt: comandă negăsită
mkcamlp5.opt: comando não encontrado
mkcamlp5.opt: commande introuvable
mkcamlp5.opt: command not found
mkcamlp5.opt: käsku ei ole
mkcamlp5.opt: không tìm thấy lệnh
mkcamlp5.opt: komanda nerasta
mkcamlp5.opt: Kommando nicht gefunden.
mkcamlp5.opt: kommandot finns inte
mkcamlp5.opt: komut yok
mkcamlp5.opt: nie znaleziono polecenia
mkcamlp5.opt: níor aimsíodh an t-ordú
mkcamlp5.opt: no se encontró la orden
mkcamlp5.opt: no s'ha trobat l'ordre
mkcamlp5.opt: opdracht niet gevonden
mkcamlp5.opt: parancs nem található
mkcamlp5.opt: perintah tidak ditemukan
mkcamlp5.opt: príkaz nenájdený
mkcamlp5.opt: příkaz nenalezen
mkcamlp5.opt: команда не найдена
mkcamlp5.opt: командата не е открита
mkcamlp5.opt: 命令找不到
mkcamlp5.opt: コマンドが見つかりません