a2j_control: 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 Debian possible default full paths are:

/usr/bin/a2j_control - from package: a2jmidid

You may install the required package with command apt-get install {package}

Error in other languages:
a2j_control: bevel nie gevind nie
a2j_control: comandă negăsită
a2j_control: comando não encontrado
a2j_control: commande introuvable
a2j_control: command not found
a2j_control: käsku ei ole
a2j_control: không tìm thấy lệnh
a2j_control: komanda nerasta
a2j_control: Kommando nicht gefunden.
a2j_control: kommandot finns inte
a2j_control: komut yok
a2j_control: nie znaleziono polecenia
a2j_control: níor aimsíodh an t-ordú
a2j_control: no se encontró la orden
a2j_control: no s'ha trobat l'ordre
a2j_control: opdracht niet gevonden
a2j_control: parancs nem található
a2j_control: perintah tidak ditemukan
a2j_control: príkaz nenájdený
a2j_control: příkaz nenalezen
a2j_control: команда не найдена
a2j_control: командата не е открита
a2j_control: 命令找不到
a2j_control: コマンドが見つかりません