jk-rotate: 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 CentOS possible default full paths are:

/usr/bin/jk-rotate - from package: python-modjkapi

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

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