speakupconf: 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/speakupconf - from package: speakup-tools

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