diff --git a/lib/_autoload_modules.php b/lib/_autoload_modules.php
index c4c85e4e4259e766d00a2dba73e05f69fdd2ed74..9a6d5f6c69828f29f8bec500224536050302cb0e 100644
--- a/lib/_autoload_modules.php
+++ b/lib/_autoload_modules.php
@@ -4,15 +4,16 @@
  * This file implements a autoloader for SimpleSAMLphp modules.
  *
  * @author Boy Baukema, SURFnet
+ * @author Jaime Perez <jaime.perez@uninett.no>, UNINETT
  * @package SimpleSAMLphp
  */
 
 /**
- * Autoload function for SimpleSAMLphp modules.
+ * Autoload function for SimpleSAMLphp modules following PSR-0.
  *
  * @param string $className Name of the class.
  */
-function SimpleSAML_autoload($className)
+function SimpleSAML_autoload_psr0($className)
 {
     $modulePrefixLength = strlen('sspmod_');
     $classPrefix = substr($className, 0, $modulePrefixLength);
@@ -28,11 +29,47 @@ function SimpleSAML_autoload($className)
         return;
     }
 
-    $file = SimpleSAML_Module::getModuleDir($module) . '/lib/' . str_replace('_', '/', $moduleClass) . '.php';
+    $file = SimpleSAML_Module::getModuleDir($module).'/lib/'.str_replace('_', '/', $moduleClass).'.php';
 
     if (file_exists($file)) {
         require_once($file);
     }
 }
 
-spl_autoload_register('SimpleSAML_autoload');
+
+/**
+ * Autoload function for SimpleSAMLphp modules following PSR-4.
+ *
+ * @param string $className Name of the class.
+ */
+function SimpleSAML_autoload_psr4($className)
+{
+    $elements = explode('\\', $className);
+    if ($elements[0] === '') { // class name starting with /, ignore
+        array_shift($elements);
+    }
+    if (count($elements) < 4) {
+        return; // it can't be a module
+    }
+    if (array_shift($elements) !== 'SimpleSAML') {
+        return; // the first element is not "SimpleSAML"
+    }
+    if (array_shift($elements) !== 'module') {
+        return; // the second element is not "module"
+    }
+
+    // this is a SimpleSAMLphp module following PSR-4
+    $module = array_shift($elements);
+    if (!SimpleSAML_Module::isModuleEnabled($module)) {
+        return; // module not enabled, avoid giving out any information at all
+    }
+
+    $file = SimpleSAML_Module::getModuleDir($module).'/lib/'.implode('/', $elements).'.php';
+
+    if (file_exists($file)) {
+        require_once($file);
+    }
+}
+
+spl_autoload_register('SimpleSAML_autoload_psr0');
+spl_autoload_register('SimpleSAML_autoload_psr4');