reviewboard-am: 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/reviewboard-am - from package: kdesdk-scripts

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

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