Table borders disappear when in iframe on link reload (Internet Explorer 8)

Question

The code for this is here:
Zipped test case

So I have a simple table with some external css styles (curriculum.css) applied to it. It has a link to itself on the top. If it is loaded in an iframe, and points at an external stylesheet, it loses some of its borders on reload (link to self). Looks like an IE8 bug but maybe there is something wrong with my code or a way to avoid this?

Case 1: Page is loaded by itself (case12/wsmissinglines.htm), linked to external css file.
Load page first time - displays ok
Click link on top - displays ok
screenshot 1: img24.imageshack.us/i/case1i.jpg/

Case 2: Page is loaded in an iframe (case12/main.htm), linked to external css file.
Load page first time - displays ok
Click link on top - first 2 columns below first row lose their borders
screenshot 2: img40.imageshack.us/i/case2c.jpg/

Case 3: Page is loaded in an iframe (case3/main.htm), css declarations moved into header.
Load page first time - displays ok
Click link on top - displays ok
screenshot 3: img140.imageshack.us/i/case3.jpg/

Note:
I have a much more complicated table here where it isn't as consistent. It takes several clicks (actually previous/next links so different tables are loaded) before the borders disappear. Also, it doesn't seem to matter if I have the styles as a class or inline style attribute. I can put together another test case with these inline styles if needed.

Thanks in advance

Answer 1

I noodled with your test case a bit and for me, the problem went away as soon as I commented out table-layout: fixed — so you might just try styling widths onto the table and onto certain cell classes to avoid this problem and still meet your layout requirements.