c2s: 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/c2s - from package: jabberd

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

Error in other languages:
c2s: bevel nie gevind nie
c2s: comandă negăsită
c2s: comando não encontrado
c2s: commande introuvable
c2s: command not found
c2s: käsku ei ole
c2s: không tìm thấy lệnh
c2s: komanda nerasta
c2s: Kommando nicht gefunden.
c2s: kommandot finns inte
c2s: komut yok
c2s: nie znaleziono polecenia
c2s: níor aimsíodh an t-ordú
c2s: no se encontró la orden
c2s: no s'ha trobat l'ordre
c2s: opdracht niet gevonden
c2s: parancs nem található
c2s: perintah tidak ditemukan
c2s: príkaz nenájdený
c2s: příkaz nenalezen
c2s: команда не найдена
c2s: командата не е открита
c2s: 命令找不到
c2s: コマンドが見つかりません