3.3 IE Italic Text Bug
Another bug particular to IE5&6, the problem here is that using italic text in a block element (such as a container div) can cause page layout to break because the container becomes wider than it should be. The exact cause of the problem is unknown but seems triggered when an italic word is used at the beginning or end of a line. It is also more frequent the more italic text is used, especially in conjunction with justified text, and font family may also take a role.
It doesn't even matter how the italic text is obtained, whether using the <i> tag in the html document or using CSS (e.g. <p class="emphasis"> - where .emphasis is defined in the stylesheet as having italic text).
Fixes
The fixes to this are rather lengthy - take a look at this website for example. Perhaps the easiest fix is to avoid using italic text, play around with the fon-family being used, and to apply generous padding the any containers that the offending text will be used in.