Widget Order by user

Creating an iGoogle-like (or Facebook-like) widget-based site where the users can log in and rearrange the various widgets we have on the site. Whenever a user rearranges the widgets, I fire off an AJAX request back to an action function that saves the sidebar/widget info into a user_meta field.

This is working fantastically when testing with a single user, but the problem comes in when multiple users rearrange things.

I know the problem revolves around my use of wp_set_sidebars_widgets() since that’s a global function. I’ve been trying to call it in both the ‘widgets_init’ action function and at the top of functions.php to make sure that the widget orders are being set for the logged-in user before it initializes them.

Is there a simple solution to having user-specific widget orders?