sieve2scm: 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/sieve2scm - from package: mailutils-guile

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

Error in other languages:
sieve2scm: bevel nie gevind nie
sieve2scm: comandă negăsită
sieve2scm: comando não encontrado
sieve2scm: commande introuvable
sieve2scm: command not found
sieve2scm: käsku ei ole
sieve2scm: không tìm thấy lệnh
sieve2scm: komanda nerasta
sieve2scm: Kommando nicht gefunden.
sieve2scm: kommandot finns inte
sieve2scm: komut yok
sieve2scm: nie znaleziono polecenia
sieve2scm: níor aimsíodh an t-ordú
sieve2scm: no se encontró la orden
sieve2scm: no s'ha trobat l'ordre
sieve2scm: opdracht niet gevonden
sieve2scm: parancs nem található
sieve2scm: perintah tidak ditemukan
sieve2scm: príkaz nenájdený
sieve2scm: příkaz nenalezen
sieve2scm: команда не найдена
sieve2scm: командата не е открита
sieve2scm: 命令找不到
sieve2scm: コマンドが見つかりません