mkgeo_ball: 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/mkgeo_ball - from package: rheolef

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