ejabberdctl: command not found

Have You tried accessing the binary with the full path?

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 Debian possible default full paths are:

/usr/sbin/ejabberdctl - from package: ejabberd

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