Dutch hacker Dimitri appears to have hacked into a Microsoft Web server for the second time in five days, where he left a message that mocked the software giant's security policy.

The 19-year-old student said he uploaded a file called oopsididitagain.htm to http://events.microsoft.com. The contents of the file read: "Patching your systems is very hard, huh," and were displayed on the Microsoft site in a large font.

In a smaller font, Dimitri complemented his idol Britney Spears for a pop concert she gave last Saturday, saying, "MSG to Britney Spears: I loved your concert in the Netherlands."

By about 10.20 PM Microsoft had apparently got wind of the second hack. The company removed the file and, according to Dimitri, patched the security hole.

Asked why he had broken into Microsoft's server for a second time, Dimitri said: "Microsoft systems engineers just don't bother securing their networks. The only thing they did on Friday was remove the file I left. Basically they lied about applying patches."

On Friday, Dimitri penetrated the same Web server and left a short text-file - Hack The planet - boasting of the hack. That file was removed shortly after PC Advisor’s sister company –IDG News Service - informed Microsoft about the intrusion.

A Microsoft spokesman said at the time that Microsoft security personnel were rechecking their servers for holes to patch. (See http://www.pcadvisor.co.uk/news/display_news.cfm?NewsID=570).