xmlrpc_pstream: 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/xmlrpc_pstream - from package: xmlrpc-c-apps

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

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