--- date_api_argument_handler.inc	2011-01-03 15:39:15.000000000 +1300
+++ date_api_argument_handler.inc.fixed	2011-01-13 11:04:57.789169589 +1300
@@ -280,7 +280,7 @@ class date_api_argument_handler extends 
       if (!empty($this->query_fields)) {
         foreach ($this->query_fields as $query_field) {
           $field = $query_field['field'];
-          $this->related_table_alias = $this->query->queue_table($field['table_name'], $this->relationship);
+          $this->related_table_alias[$field['table_name']] = $this->query->queue_table($field['table_name'], $this->relationship);
         }
       }
     }
@@ -358,7 +358,7 @@ class date_api_argument_handler extends 
       foreach ($this->query_fields as $query_field) {
         $field = $query_field['field'];
         $date_handler = $query_field['date_handler'];
-        $table_alias = !empty($this->related_table_alias) ? $this->related_table_alias : $field['table_name'];
+        $table_alias = !empty($this->related_table_alias[$field['table_name']]) ? $this->related_table_alias[$field['table_name']] : $field['table_name'];
         $from_field = str_replace($field['table_name'] .'_', $table_alias .'.', $field['fromto'][0]);
         $to_field = str_replace($field['table_name'] .'_', $table_alias .'.', $field['fromto'][1]);