prove.php: 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/share/pear/symfony/plugins/sfDoctrinePlugin/test/bin/prove.php - from package: php-symfony-symfony
/usr/share/pear/symfony/plugins/sfPropelPlugin/test/bin/prove.php - from package: php-symfony-symfony

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