dspam-front: 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 CentOS possible default full paths are:

/usr/bin/dspam-front - from package: dspam

You may install the required package with command yum install {package}

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