This has been covered by the mainstream German media:

30.5.2011, Spiegel Online, Hacker kapern rechte Websites, http://www.spiegel.de/netzwelt/web/0,1518,765784,00.html

31.5.2011, sueddeutsche.de, Hacker kapern NPD-Webseiten, http://www.sueddeutsche.de/digital/attacke-auf-rechte-partei...

The NPD response, quoted in the Spiegel article, is laughable: they talk about how their security was relatively good and that there is no such thing as 100% security rather than what they are going to do for their exposed donors. With luck, this means that they will have fewer donors in future.

Just in case the point needs spelling out: for an organisation to to administer all of its 26 websites from the same machine it stores some of its most sensitive data is not relatively good security.