The latest E-Biz Diagnostic patch is 6459585 (E-Business Suite Diagnostic Pack February 2008). I came across metalink note 357745.1:
This document contains the most recent versions of the xml files used by diagnostics tools within Oracle Diagnostics. XML files are used by Oracle Support to hold data that requires being regularly updated such as maintainance packs, family packs, patches and other supporting data. These XML files are used by diagnostics tools executable in Oracle Diagnostics to verify for example if a particular family pack is installed.
In order for diagnostics tools to check your environment against the latest information available from Oracle, these xml files are updated and released on an ongoing basis. This means that the latest available xml files will always be available from this note while the latest E-Business Suite diagnostics patch will include the latest available xml files at the time of the patch build.
So, it is a good practice to visit this metalink note, if you are applying the latest diagnostic pack. As a post step you can download the latest xml files from this note and unzip them in your $IZU_TOP/html directory.