diff --git a/check.php b/check.php
index 7182bac..550f6db 100644
--- a/check.php
+++ b/check.php
@@ -30,7 +30,7 @@ class Check {
             $from_type = $page->type_info($from);
             $type = $from_type['type'];
             if ($type !== null) {
-                $href .= "&from=" . lcfirst($from_type['title']);
+                $href .= "&from=" . Page::lc_first($from_type['title']);
             }
 
             echo "<br><script type=\"text/javascript\">document.location=\"$href\";</script>";
diff --git a/history.php b/history.php
index baf372a..3488e56 100644
--- a/history.php
+++ b/history.php
@@ -95,7 +95,7 @@ if (isset($_GET['from'])) {
     $info = $page->type_info($_GET['from']);
     if ($info['type'] !== null) {
         $from_title = $info['title'];
-        $from = lcfirst($from_title);
+        $from = Page::lc_first($from_title);
         $from_href = "$from.php";
     }
 }
diff --git a/inc/page.php b/inc/page.php
index 082b3f2..f012e88 100644
--- a/inc/page.php
+++ b/inc/page.php
@@ -390,4 +390,14 @@ class Page {
             echo "<script type=\"text/javascript\">withjQuery(function(){ $('tr').click(function(){var href=$(this).find('a').attr('href');if(href!==undefined)window.location=href;}).hover(function(){\$(this).toggleClass('hover');}); });</script>";
         }
     }
+
+    /**
+     * lcfirst is only supported in PHP >= 5.3
+     * @param $str
+     * @return string
+     */
+    static function lc_first($str) {
+        $str[0] = strtolower($str[0]);
+        return (string)$str;
+    }
 }