bounced: 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/bin/bounced - from package: sympa

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