diff -Naur og_menu.old/og_menu.module og_menu/og_menu.module
--- og_menu.old/og_menu.module	2010-01-23 22:14:41.000000000 +0000
+++ og_menu/og_menu.module	2010-01-23 22:09:09.000000000 +0000
@@ -225,7 +225,13 @@
       }
       // Otherwise, the user may only set to one group.
       elseif (!empty($form['og_nodeapi']['invisible']['og_groups'])) {
-        $groups[] = $form['og_nodeapi']['invisible']['og_groups']['#value'];
+        $groups1 = $form['og_nodeapi']['invisible']['og_groups']['#value'];
+          if (is_array($groups1)) {
+            $groups[] = array_shift(array_keys($groups1));
+          }
+          else {
+            $groups[] = $groups1;
+          }
       }
 
       $list = array();