I guess it'd help you to know that I totally ignored Internet Explorer until Chapter 18.
The problems you're having have to do with the fact that Explorer 6 doesn't support the adjacent sibling selectors in the rule "h4 + p" and "h5 + p".
In Chapter 18 I present how to implement a javascript called "IE7", which brings CSS 2 selector support to Internet Explorer 5, 5.5 and 6 (among other things that Explorer doesn't support natively).
My reasoning behind this was that I wanted to demonstrate how CSS works in browsers having the most CSS support possible. Though I recognize this isn't very useful since 90% of the world uses IE6 to browse the internet. I addressed that by giving Internet Explorer a Chapter of its own at the end of the book that demonstrates common CSS bugs, and how to use Dean Edwards's IE7 JavaScript to increase CSS support in IE without your users needing to upgrade or do anything on their end. After Chapter 18, the JT's website looks pretty much the same between IE 5.5, IE 6, Firefox, Opera, et all. Though admitedly, I was using an earlier version of the IE7 javascript when I wrote the book, so some things may have changed since then using a newer, faster, more stable version of that javascript.
Let me know if you have any more questions.
Regards,
Rich
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