Force a page over ssl (Admin SSL plugin not working)

Hi!

I really need to get a page running over SSL.

I tried adding this to my header file:

<?php
if(is_page('purchase-a-share'))
{
	if($_SERVER["HTTPS"] != "on")
	{
		$newurl = "https://www.mysite.org/purchase-a-share";
		header("Location: $newurl");
		exit();
	}
}
?>

That does not work because some of the content is not authenticated (since wordpress echo’s out https:// paths).

I also tried the Admin SSL plugin. I’m using WP 2.8 and it’s not working – it’s causing a redirect loop.

So, does anyone have a solution for this?

Thanks in advance