gloox-config: 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/gloox-config - from package: gloox-devel

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

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