Index: og.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/og/Attic/og.module,v
retrieving revision 1.628.4.48
diff -u -p -r1.628.4.48 og.module
--- og.module	7 Nov 2010 17:37:26 -0000	1.628.4.48
+++ og.module	15 Dec 2010 04:55:19 -0000
@@ -721,7 +721,15 @@ function og_set_group_context($node = NU
   if (!empty($node) && og_is_group_type($node->type)) {
     $stored_group_node = $node;
     og_set_theme($node);
-    og_set_language($node);
+    // When setting the language, avoid doing so if we are on a node page
+    // and the language of the node is different to the language of the
+    // group. This covers the case when the site doesn't have a prefix for
+    // the default language, particularly if the same node is posted in
+    // multiple groups.
+    $current_node = menu_get_object();
+    if (!$current_node || (!og_is_group_type($current_node->type) && $current_node->language == $node->group_language)) {
+      og_set_language($node);
+    }
   }
   return !empty($stored_group_node) ? $stored_group_node : NULL;
 }