newnfsvserver: 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/sbin/newnfsvserver - from package: vserver-debiantools

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

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