Found by way of a WebmasterWorld featured post, an article named Basis Technology Enhances Multilingual Search in MSN Search Engine. An other, more detailed article on this can be found at Yahoo! News, which is basically a copy of the offical press release.
The Rosette Linguistics Platform provides MSN the ability to better handle foreign languages. One example is the quote all news and forums are using from the release:
Rosette performs linguistic analysis that helps information retrieval applications understand search queries. For example, Rosette identifies individual words for languages such as Japanese that do not use spaces between words, breaks compound words into their individual components, and identifies parts-of-speech such as verb, adjective, etc. This information increases the accuracy of search results.
This is also common in German, where they often join two words into one (i think), such as "webdesign". An other useful quote from the press release is "The Rosette Linguistics Platform uses state of the art Natural Language Processing techniques to improve information retrieval, text mining and other applications and apply them to global markets. Rosette provides capabilities like identifying the language of incoming text, providing a normalized representation in Unicode, and locating names, places and other key concepts."
MSN, looking good.