Index: includes/context.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/drush/includes/context.inc,v
retrieving revision 1.15
diff -u -r1.15 context.inc
--- includes/context.inc	6 Dec 2009 12:53:38 -0000	1.15
+++ includes/context.inc	7 Dec 2009 19:01:30 -0000
@@ -113,8 +113,11 @@
  */
 function drush_load_config($context) {
   global $drush_conf_override;
-  
-  $drush_conf_override = array();
+
+  // Only reset $drush_conf_override if the array is not set, otherwise keep old values and append new values to it.
+  if (!isset($drush_conf_override)) {
+    $drush_conf_override = array();
+  }
 
   $config = _drush_config_file($context);
   if (file_exists($config)) {