fb_lock_print: 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/sbin/fb_lock_print - from package: firebird

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

On Debian possible default full paths are:

/usr/sbin/fb_lock_print - from package: firebird2.5-classic-common
/usr/sbin/fb_lock_print - from package: firebird2.5-super

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

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