"As a member of the Germanic family of languages, English is unusual in that even simple compounds made since the 18th century tend to be written in separate parts. This would be an error in other Germanic languages such as [...] German, and Dutch. However, this is merely an orthographic convention."
And this also:
" In Dutch and the Scandinavian languages there is an unofficial trend toward splitting compound words, known in Norwegian as særskriving, in Swedish as särskrivning (literally "separate writing"), and in Dutch as Engelse ziekte (the "English disease"). Because the Dutch language and the Scandinavian languages rely heavily on the distinction between the compound word and the sequence of the separate words it consists of, this has serious implications. In Dutch, compounds written with spaces may also be confused, but can also be interpreted as a sequence of a noun and a genitive (which is unmarked in Dutch) in formal abbreviated writing. This may lead to, for example, commissie vergadering ("commission meeting") being read as "commission of the meeting" rather than "meeting of the commission" (normally spelled commissievergadering). "