Solved, I need specify $keyConfig for OpenSSL function :
$keyConfig = array(
'config' => dirname($_SERVER['SCRIPT_FILENAME']) . '/store/openssl.cnf',
...
);
$sslConfig = array(
"countryName" => 'XX',
"stateOrProvinceName" => 'XX',
"localityName" => 'XX',
...
);
$pKey = openssl_pkey_new( $keyConfig );
$pCSR = openssl_csr_new( $sslConfig, $pKey , $keyConfig );
$pCRT = openssl_csr_sign( $pCSR , null , $pKey , self::TIME_INTERVAL_WEEK , $keyConfig );
openssl_x509_export( $pCRT, $strCertificate );
openssl_pkey_export( $pKey, $strPrivateKey , null , $keyConfig );