Breadcrumbs and drop down menus broken in header after upgrading to Java JDK 7

Refer to the screenshot below:

Dynamic menus are broken, along with some broken formatting, not too sure exactly how to explain it in words, but the screenshot should suffice.

Tested and reproducible across FF, Chrome, and IE9.

Workaround

Shutdown Confluence, then remove the following folders from the Confluence Home Directory:

1. bundled-plugins
2. plugins-cache
3. plugins-osgi-cache
4. plugins-temp