I read this today: http://news.com.com/No%20fix%20for%2...l?tag=nefd.top
If you read the corresponding 'Microsoft Security Bulletin MS06-015' (Link) you'll come across this passage:
Translated into plain English they are really saying:The Microsoft Windows 98, Microsoft Windows 98 Second Edition (SE), and Microsoft Windows Millennium Edition (ME) Windows Explorer architecture is much less robust than the more recent Windows architectures. Due to these fundamental differences, after extensive investigation, Microsoft has found that it is not feasible to make the extensive changes necessary to Windows Explorer on Microsoft Windows 98, Microsoft Windows 98 Second Edition (SE), and Microsoft Windows Millennium Edition (ME) to eliminate the vulnerability. To do so would require reengineer a significant amount of a critical core component of the operating system. After such a reengineering effort, there would be no assurance that applications designed to run on these platforms would continue to operate on the updated system.
Windows 98 code is a mess and this bug goes really deep. We don't really understand the stuff we coded back then and we can't fix it anymore. We tried and the whole thing broke. So we rather leave it and recommend you buy a licence for a newer Windows version.
Are they serious? They should be so ashamed of themselves.