rpm2mpm: 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/rpm2mpm - from package: rhnpush

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

Error in other languages:
rpm2mpm: bevel nie gevind nie
rpm2mpm: comandă negăsită
rpm2mpm: comando não encontrado
rpm2mpm: commande introuvable
rpm2mpm: command not found
rpm2mpm: käsku ei ole
rpm2mpm: không tìm thấy lệnh
rpm2mpm: komanda nerasta
rpm2mpm: Kommando nicht gefunden.
rpm2mpm: kommandot finns inte
rpm2mpm: komut yok
rpm2mpm: nie znaleziono polecenia
rpm2mpm: níor aimsíodh an t-ordú
rpm2mpm: no se encontró la orden
rpm2mpm: no s'ha trobat l'ordre
rpm2mpm: opdracht niet gevonden
rpm2mpm: parancs nem található
rpm2mpm: perintah tidak ditemukan
rpm2mpm: príkaz nenájdený
rpm2mpm: příkaz nenalezen
rpm2mpm: команда не найдена
rpm2mpm: командата не е открита
rpm2mpm: 命令找不到
rpm2mpm: コマンドが見つかりません