cdtoa: 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/cdtoa - from package: freewnn-cserver

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