Using images to create page border

Hi, I'm using images to create a border around my pages.

To create the border around the content area, I have a background image repeated vertically down the left side bar. It's also the same down the right side bar.

This trick works in every browser except Opera (latest). In Opera, it looks like the tables for the LSB and RSB are not at 100% height. When I add some text, the LSB and RSB extend as far as the text go.

How can I get this to work with Opera?

Or is there an easier way to put in the images as borders?

Thanks!