diff --git a/include/class.i18n.php b/include/class.i18n.php
index a06edbae1319a0e9b314b476111aa3e6afe466ea..884dc7cb9863f51e796e5fe812c03eeb67d697ab 100644
--- a/include/class.i18n.php
+++ b/include/class.i18n.php
@@ -306,7 +306,8 @@ class DataTemplate {
                 $this->filepath = Misc::realpath("{$this->base}/$l/$path");
                 break;
             }
-            elseif (Phar::isValidPharFilename("{$this->base}/$l.phar")
+            elseif (class_exists('Phar')
+                    && Phar::isValidPharFilename("{$this->base}/$l.phar")
                     && file_exists("phar://{$this->base}/$l.phar/$path")) {
                 $this->lang = $l;
                 $this->filepath = "phar://{$this->base}/$l.phar/$path";
diff --git a/include/class.plugin.php b/include/class.plugin.php
index 7e1a2b228bdcc9f7e4379c15ec4e8190d66859cf..ffa86b614161cb15b9ea9b418155b1d7f2c0e208 100644
--- a/include/class.plugin.php
+++ b/include/class.plugin.php
@@ -192,6 +192,7 @@ class PluginManager {
                 GLOB_NOSORT|GLOB_BRACE) as $p) {
             $is_phar = false;
             if (substr($p, strlen($p) - 5) == '.phar'
+                    && class_exists('Phar')
                     && Phar::isValidPharFilename($p)) {
                 try {
                 // When public key is invalid, openssl throws a
diff --git a/include/staff/system.inc.php b/include/staff/system.inc.php
index f1fb08204dfe49f61f4bfb5a8a1f7357be47fa11..6532762fc8f77faf737f696094871f91fd04b5ea 100644
--- a/include/staff/system.inc.php
+++ b/include/staff/system.inc.php
@@ -51,6 +51,21 @@ $commit = GIT_VERSION != '$git' ? GIT_VERSION : (
                     echo extension_loaded('mbstring')?'check':'warning-sign'; ?>"></i></td>
                 <td>mbstring</td>
                 <td>Highly recommended for non western european language content</td></tr>
+            <tr><td><i class="icon icon-<?php
+                    echo extension_loaded('phar')?'check':'warning-sign'; ?>"></i></td>
+                <td>phar</td>
+                <td>Highly recommended for plugins and language packs</td></tr>
+        </tbody></table></td></tr>
+    <tr><td>PHP Settings</td>
+        <td><table><tbody>
+        <tr><td><i class="icon icon-<?php
+                echo extension_loaded('mbstring')?'check':'warning-sign'; ?>"></i>
+            </td><td>
+            <code>cgi.fix_pathinfo</code> =
+                <?php echo ini_get('cgi.fix_pathinfo'); ?>
+            </td><td>
+            <span class="faded">"1" is recommended if AJAX is not working</span>
+        </td></tr>
         </tbody></table></td></tr>
 </tbody>
 <thead>
diff --git a/setup/inc/install-prereq.inc.php b/setup/inc/install-prereq.inc.php
index f004ba6883fbd858e51f09fc2db92edadddc6cc0..fa86058ba3744075b8d933d0317d3f5d90aaee2b 100644
--- a/setup/inc/install-prereq.inc.php
+++ b/setup/inc/install-prereq.inc.php
@@ -29,6 +29,7 @@ if(!defined('SETUPINC')) die('Kwaheri!');
                 <li class="<?php echo extension_loaded('json')?'yes':'no'; ?>">PHP JSON extension (faster performance)</li>
                 <li class="<?php echo extension_loaded('gettext')?'yes':'no'; ?>">Gettext is used for translations (faster performance)</li>
                 <li class="<?php echo extension_loaded('mbstring')?'yes':'no'; ?>">Mbstring is <b>strongly</b> recommended for all installations</li>
+                <li class="<?php echo extension_loaded('phar')?'yes':'no'; ?>">Phar is <b>strongly</b> recommended for plugins and language packs</li>
             </ul>
             <div id="bar">
                 <form method="post" action="install.php">
diff --git a/setup/test/tests/stubs.php b/setup/test/tests/stubs.php
index e41ac16d32d35c48b21b11b77ac0ac2fc4af6ff3..9479e274486467ffd000bbe7be06690911faa39e 100644
--- a/setup/test/tests/stubs.php
+++ b/setup/test/tests/stubs.php
@@ -96,9 +96,9 @@ class Phar {
 
 class ZipArchive {
     function statIndex() {}
+    function addFromString() {}
     function getFromIndex() {}
     function setCommentName() {}
-    function addFromString() {}
 }
 
 class finfo {