epspdftk: 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/epspdftk - from package: texlive-pictures

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

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