prototype.js Ajax.updater

[Jeff]

I'd like to use Ajax.updater to update a container whose id is
generated dynamically. Here was my first thought:

function getEditor(id) {
var url = '/include/helper.php';
var prm = 'what=editor&id='+id;
var ajx = new Ajax.Updater(id, url, { method: 'get', parameters: prm
});
}

That fails. If I hardcode the container it works fine:

function getEditor(id) {
var url = '/include/helper.php';
var prm = 'what=editor&id='+id;
var ajx = new Ajax.Updater('1000', url, { method: 'get', parameters:
prm });
}

This works.

Any thoughts?