Passing parameters to a web popup

Is it possible to pass parameters to a web popup that’s using a local HTML file i.e. as a query string with the URL? I’ve tried using Javascript functions in the HTML file to pick up the qyuery string parameters but I can’t get an onload function to fire. Is this supported?

Stefan [import]uid: 2646 topic_id: 9161 reply_id: 309161[/import]