How to display double line borders on tables
MacBook Air, OS X Mavericks (10.9)
There is no double-line border style in Pages v5+. You can use the line shape, blue guides, and arrow keys to place a line adjacent to top and bottom borders. Set Arrange to Stay on Page, select the line segments and table, then group. This is external, but can be pulled inside the table for improved appearance.
Dylan,
Apparently that is a MS Word option in tables. iWork can't handle it. I don't think it's a firm requirement. In searching other IEEE documents, I found others without the double line.
Never the less, I was able do duplicate the look by just setting multiple tables adjacent with just enough space between them to make two single borders appear as one double border. I did this in Pages '09, which I find easier to work in.
Jerry
How to display double line borders on tables