How can I tell when Safari on iPad is using HTTPS Safari hides the protocol part of the URL (HTTP or HTTPS) in the address bar.

When I'm purchasing something on the Internet, I like to check that I'm using HTTPS when entering credit card details or entering a username and password.

I don't seem to be able to do this when using Safari on my iPad.
There should be a padlock before the page title at the top of the screen when you're on an https page.