gaterm: command not found

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/gaterm - from package: aterm-ml

You may install the required package with command apt-get install {package}

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