kytea: 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/kytea - from package: kytea

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