forge_run_plugin_job: 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/forge_run_plugin_job - from package: gforge-common
/usr/share/gforge/bin/forge_run_plugin_job - from package: gforge-common

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

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