rst2xml: 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/rst2xml - from package: python-docutils

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

Error in other languages:
rst2xml: bevel nie gevind nie
rst2xml: comandă negăsită
rst2xml: comando não encontrado
rst2xml: commande introuvable
rst2xml: command not found
rst2xml: käsku ei ole
rst2xml: không tìm thấy lệnh
rst2xml: komanda nerasta
rst2xml: Kommando nicht gefunden.
rst2xml: kommandot finns inte
rst2xml: komut yok
rst2xml: nie znaleziono polecenia
rst2xml: níor aimsíodh an t-ordú
rst2xml: no se encontró la orden
rst2xml: no s'ha trobat l'ordre
rst2xml: opdracht niet gevonden
rst2xml: parancs nem található
rst2xml: perintah tidak ditemukan
rst2xml: príkaz nenájdený
rst2xml: příkaz nenalezen
rst2xml: команда не найдена
rst2xml: командата не е открита
rst2xml: 命令找不到
rst2xml: コマンドが見つかりません