spfmilter.py: 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/spfmilter.py - from package: spf-milter-python

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

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