jbibtex: 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/jbibtex - from package: texlive-east-asian

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

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