diff --git a/httprl.install b/httprl.install
index 2c8ca58..0189757 100644
--- a/httprl.install
+++ b/httprl.install
@@ -47,7 +47,7 @@ function httprl_requirements($phase) {
     // Check each function to make sure it exists.
     foreach ($function_list as $function_name) {
       if (!function_exists($function_name)) {
-        $requirements['httprl-function-' . $function_name] = array(
+        $requirements['httprl_function_' . $function_name] = array(
           'title' => $t('HTTPRL'),
           'value' => $phase == 'install' ? FALSE : $function_name,
           'severity' => REQUIREMENT_ERROR,
@@ -58,15 +58,72 @@ function httprl_requirements($phase) {
         );
       }
     }
+  }
+  if ($phase == 'runtime') {
+    $url_path = 'admin/httprl-test';
+    // Check that the menu router handler is working. If it's not working the rest
+    // of the tests are pointless.
+    $item = menu_get_item($url_path);
+    if (empty($item['page_callback']) || strpos($item['page_callback'], 'httprl') === FALSE) {
+      $item = str_replace('    ', '    ', nl2br(htmlentities(print_r($item, TRUE))));
+      $requirements['httprl_callback'] = array(
+        'title'       => $t('HTTPRL - Menu Callback'),
+        'severity'    => REQUIREMENT_WARNING,
+        'value'       => $t('Flush your caches'),
+        'description' => $t('You need to flush your menu cache. The test callback for httprl is not there.'),
+      );
+      return $requirements;
+    }
+
+    // Test the non blocking url
+    global $base_root, $base_path;
+    // Build URL to point to admin/httprl-test on this server.
+    $ip = empty($_SERVER['SERVER_ADDR']) ? '127.0.0.1' : $_SERVER['SERVER_ADDR'];
+    $id = 'httprl_' . md5(mt_rand() . time());
+    $url_ip = 'http://' . $ip . $base_path . $url_path . '?key=' . md5(drupal_get_private_key()) . '&id=' . $id;
+    $url_host = $base_root . $base_path . $url_path . '?key=' . md5(drupal_get_private_key()) . '&id=' . $id;
+    // Set the headers to point to this hostname.
+    $headers = array(
+      'Host' => $_SERVER['HTTP_HOST'],
+    );
+
+    // Add in the headers and set the blocking mode.
+    $options = array(
+      'headers' => $headers,
+      'blocking' => FALSE,
+      'timeout' => 6.0,
+    );
+
+    // Start the timer & Get a lock.
+    timer_start($id);
+    lock_acquire($id, 6);
+
+    // Queue up the requests & execute them.
+    httprl_request($url_ip, $options);
+    httprl_request($url_host, $options);
+    $requests = httprl_send_request();
 
-    if (empty($requirements)) {
-      $requirements['httprl'] = array(
-        'title'     => $t('HTTPRL'),
-        'severity'  => REQUIREMENT_OK,
-        'value'     => $phase == 'install' ? TRUE : $t('All the required functions are enabled.'),
+    // Wait for the lock and stop the timer.
+    lock_wait($id);
+    $time = timer_stop($id);
+    if (($time['time'] / 1000) > 5) {
+      // Lock timed out and was not reset by the URL ping.
+      $requirements['httprl_nonblocking'] = array(
+        'title'       => $t('HTTPRL - Non Blocking'),
+        'severity'    => REQUIREMENT_WARNING,
+        'value'       => $t('This server does not handle hanging connections.'),
+        'description' => $t('Using non blocking mode on this server my not work correctly. More info: !info', array('!info' => str_replace('    ', '    ', nl2br(htmlentities(print_r(array($time, $requests), TRUE)))))),
       );
     }
   }
 
+  if (empty($requirements)) {
+    $requirements['httprl'] = array(
+      'title'     => $t('HTTPRL'),
+      'severity'  => REQUIREMENT_OK,
+      'value'     => $phase == 'install' ? TRUE : $t('All the required functions are enabled and non blocking requests are working.'),
+    );
+  }
+
   return $requirements;
 }
diff --git a/httprl.module b/httprl.module
index b3b2298..04b38e1 100755
--- a/httprl.module
+++ b/httprl.module
@@ -6,9 +6,29 @@
  *
  */
 
+/**
+ * Error code indicating that the request made by httprl_send_request() failed
+ * to write to the open stream.
+ */
 define('HTTP_REQUEST_FWRITE_FAIL', -2);
 
 /**
+ * Implement hook_menu().
+ */
+function httprl_menu() {
+  $items = array();
+  $items['admin/httprl-test'] = array(
+    'title' => 'HTTPRL',
+    'page callback' => 'httprl_nonblockingtest_page',
+    'access callback' => TRUE,
+    'description' => 'Ajax callback for view loading.',
+    'type' => MENU_CALLBACK,
+    'file' => 'httprl.nonblocktest.inc',
+  );
+  return $items;
+}
+
+/**
  * Perform an HTTP request
  *
  * @see drupal_http_request()
diff --git a/httprl.nonblocktest.inc b/httprl.nonblocktest.inc
new file mode 100644
index 0000000..a97f150
--- /dev/null
+++ b/httprl.nonblocktest.inc
@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * Menu Callback; Release a lock if the right conditions are met.
+ */
+function httprl_nonblockingtest_page() {
+  // exit if
+  //  The id is not set.
+  //  The key is not set.
+  //  The id does not start with httprl_.
+  //  The key does not match the md5 of drupal_get_private_key().
+  if (   empty($_GET['id'])
+      || empty($_GET['key'])
+      || strpos($_GET['id'], 'httprl_') !== 0
+      || $_GET['key'] != md5(drupal_get_private_key())
+        ) {
+    exit;
+  }
+
+  // Release the lock, echo out that the lock was cleared and exit.
+  lock_release($_GET['id']);
+  echo t('lock @id cleared', array('@id' => $_GET['id']));
+  exit;
+}