resque / php-resque

demo/queue.php

<?php
if(empty($argv[1])) {
	die('Specify the name of a job to add. e.g, php queue.php PHP_Job');
}

require __DIR__ . '/init.php';
date_default_timezone_set('GMT');
Resque::setBackend('127.0.0.1:6379');

// You can also use a DSN-style format:
//Resque::setBackend('redis://user:pass@127.0.0.1:6379');
//Resque::setBackend('redis://user:pass@a.host.name:3432/2');

$args = array(
	'time' => time(),
	'array' => array(
		'test' => 'test',
	),
);
if (empty($argv[2])) {
	$jobId = Resque::enqueue('default', $argv[1], $args, true);
} else {
        $jobId = Resque::enqueue($argv[1], $argv[2], $args, true);	
}

echo "Queued job ".$jobId."\n\n";

Are you sure $jobId of type false|string can be used in concatenation?