Reloading a specific window

Warning for server side purists: My php scripts use javascript to popup and close windows. So this question, although posted to a php newsgroup, has elements of javascript too. Gasp! No flames please. I have a main window which I will refer to as mainwindow (window.name='mainwindow' in the onload event). The script loaded into it is mainListing.php. From mainListing.php I popup another window, with a form and a save button. The form's action is "action.php" In action.php I update the database and then would like to: (1) refresh mainwindow so it reflects the database changes, and (2) close the popup window. I have been reading, tweaking, trying different things but nothing is working. Currently, the action script does: ... elseif (isset($_POST['btnSave'])) { .. update the database, then ... header("Location: ".$_POST['CallingScript']."?ID=".$_POST['ID']); exit; } ... This reloads the popup window, and then I have a "close" button to close the popup. Then I have to refresh the browser window manually to see the updated table from the database. Can I get some advice on how to accomplish (1) and (2) above? Many thanks, Rich