pmkinstall: 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/pmkinstall - from package: pmk

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

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