diff -ur drupal-6.11.dist/includes/database.inc drupal-6.11/includes/database.inc
--- drupal-6.11.dist/includes/database.inc	2009-02-16 15:41:58.000000000 +0100
+++ drupal-6.11/includes/database.inc	2009-04-30 14:24:56.000000000 +0200
@@ -95,11 +95,14 @@
       foreach ($db_prefix as $key => $val) {
         $sql = strtr($sql, array('{'. $key .'}' => $val . $key));
       }
-      return strtr($sql, array('{' => '', '}' => ''));
+			return strtr($sql, array('{' => '', '}' => ''));
     }
   }
   else {
-    return strtr($sql, array('{' => $db_prefix, '}' => ''));
+		$s = strtr($sql, array('{' => $db_prefix, '}' => ''));
+		$s = preg_replace( '/CREATE +INDEX +\w+\./i', 'CREATE INDEX ', $s );
+		$s = preg_replace( '/CONSTRAINT +\w+\./i', 'CONSTRAINT ', $s );
+		return $s;
   }
 }