mpdsigjob: 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/mpdsigjob - from package: mpich2

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

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