I have the shared SSL offered through

. When I ran a test transaction, every time I went to the next step, I got the "This page contains both secure and non-secure items" warning. I assume that has to do with my images (banner and so-forth), but how does that get fixed? I don't want that warning popping up for the customers and scaring them away.
I apologize if this is something that is in the manual, but it's 4 am and I'm a little bleary-eyed from poking at it all evening.