dspam_pg2int8: 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 CentOS possible default full paths are:

/usr/bin/dspam_pg2int8 - from package: dspam-pgsql

You may install the required package with command yum install {package}
Error in other languages:
dspam_pg2int8: bevel nie gevind nie
dspam_pg2int8: comandă negăsită
dspam_pg2int8: comando não encontrado
dspam_pg2int8: commande introuvable
dspam_pg2int8: command not found
dspam_pg2int8: käsku ei ole
dspam_pg2int8: không tìm thấy lệnh
dspam_pg2int8: komanda nerasta
dspam_pg2int8: Kommando nicht gefunden.
dspam_pg2int8: kommandot finns inte
dspam_pg2int8: komut yok
dspam_pg2int8: nie znaleziono polecenia
dspam_pg2int8: níor aimsíodh an t-ordú
dspam_pg2int8: no se encontró la orden
dspam_pg2int8: no s'ha trobat l'ordre
dspam_pg2int8: opdracht niet gevonden
dspam_pg2int8: parancs nem található
dspam_pg2int8: perintah tidak ditemukan
dspam_pg2int8: príkaz nenájdený
dspam_pg2int8: příkaz nenalezen
dspam_pg2int8: команда не найдена
dspam_pg2int8: командата не е открита
dspam_pg2int8: 命令找不到
dspam_pg2int8: コマンドが見つかりません