diff --git a/Makefile b/Makefile
index 066af11f2298cd7a92f65ad814ff368a13c7a7a7..34ac41a296193cdc923242899206c81f28985926 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 BASE=ordernumber
 PLUGINTYPE=vmshopper
-VERSION=3.6
+VERSION=3.6a
 
 PLUGINFILES=$(BASE).php $(BASE).script.php $(BASE).xml index.html $(BASE)/
 
diff --git a/ordernumber.php b/ordernumber.php
index 5d328f3d8d7b4b49a5a12cd051f12235625bdcbb..b1e42bd7fb10f28eea4a82b4c46032abc96f3299 100644
--- a/ordernumber.php
+++ b/ordernumber.php
@@ -356,11 +356,14 @@ class plgVmShopperOrdernumber extends vmShopperPlugin {
         }
     }
     
+	protected function no_array($v) {
+		return !is_array($v);
+	}
     protected function doReplacements ($fmt, $reps) {
         // First, replace all random...[n] fields. This needs to be done with a regexp and a callback:
         $fmt = preg_replace_callback ('/\[(random)(.*?)([0-9]*?)\]/', array($this, 'replaceRandom'), $fmt);
         // Only use string-valued variables for replacement (array-valued variables can be used in custom variable definitions!)
-        $reps = array_filter($reps, function($v) { return !is_array($v);} );
+        $reps = array_filter($reps, array($this, "no_array") );
         return str_ireplace (array_keys($reps), array_values($reps), $fmt);
     }
     
diff --git a/ordernumber.xml b/ordernumber.xml
index 4cc89a4a804753a70c296fbbe502897cefdf5321..96cd9bca8d5d4360224b3c87ebd9656c44dce12c 100644
--- a/ordernumber.xml
+++ b/ordernumber.xml
@@ -7,7 +7,7 @@
     <authorUrl>http://www.open-tools.net/</authorUrl>
     <copyright>Copyright (C) 2012-2015 Reinhold Kainhofer. All rights reserved.</copyright>
     <license>http://www.gnu.org/licenses/gpl-3.0.html GNU/GPLv3</license>
-    <version>3.6</version>
+    <version>3.6a</version>
     <releaseDate>2015-05-23</releaseDate>
     <releaseType>Minor update</releaseType>
     <downloadUrl>http://open-tools.net/virtuemart/advanced-ordernumbers.html</downloadUrl>
diff --git a/releases/plg_vmshopper_ordernumber_v3.6a.zip b/releases/plg_vmshopper_ordernumber_v3.6a.zip
new file mode 100644
index 0000000000000000000000000000000000000000..8843e81ff5ee691359de9bb7e9f0cdb454963489
Binary files /dev/null and b/releases/plg_vmshopper_ordernumber_v3.6a.zip differ