content markup for languages

Our confluence site currently hosts pages which are written in german, english and occassionaly spanish or russian. Everybody has its own take on how to put multiple languages on one page. Unfortunately there is no markup to specify a language for a content area. Also page titles would have to either respect this markup or use additional metadata.

A macro in the style of

which displays content based on the users or default site language would probably be easy to implement.

Textile however provides a nice way to create spans which can be supplied with a language attribute. The introduction of spans in wiki syntax would also provide powerful formatting possibilities without having to resort to HTML-like syntax like some plugins do.
Here is how spans in german and english would look like:
%[de-DE]Ein Paragraph in Deutsch%
%[en-EN]A paragraph in english%
You can try the full textile notation at http://textism.com/tools/textile/index.php

Another approach would be to specify a language for the whole page. In practise this would be very impractical because often only parts of the page need to be translated, for example a summary. Other content like a spare parts list and the page structure are language neutral.