kdeinit4_shutdown: 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 CentOS possible default full paths are:

/usr/bin/kdeinit4_shutdown - from package: kdelibs

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/kdeinit4_shutdown - from package: kdelibs-bin

You may install the required package with command apt-get install {package}
Error in other languages:
kdeinit4_shutdown: bevel nie gevind nie
kdeinit4_shutdown: comandă negăsită
kdeinit4_shutdown: comando não encontrado
kdeinit4_shutdown: commande introuvable
kdeinit4_shutdown: command not found
kdeinit4_shutdown: käsku ei ole
kdeinit4_shutdown: không tìm thấy lệnh
kdeinit4_shutdown: komanda nerasta
kdeinit4_shutdown: Kommando nicht gefunden.
kdeinit4_shutdown: kommandot finns inte
kdeinit4_shutdown: komut yok
kdeinit4_shutdown: nie znaleziono polecenia
kdeinit4_shutdown: níor aimsíodh an t-ordú
kdeinit4_shutdown: no se encontró la orden
kdeinit4_shutdown: no s'ha trobat l'ordre
kdeinit4_shutdown: opdracht niet gevonden
kdeinit4_shutdown: parancs nem található
kdeinit4_shutdown: perintah tidak ditemukan
kdeinit4_shutdown: príkaz nenájdený
kdeinit4_shutdown: příkaz nenalezen
kdeinit4_shutdown: команда не найдена
kdeinit4_shutdown: командата не е открита
kdeinit4_shutdown: 命令找不到
kdeinit4_shutdown: コマンドが見つかりません