BitchX: 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/BitchX - from package: BitchX

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

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