If, like me, you're a regular user of the "Unread Messages" link (at
http://forum.dokuwiki.org/ at top right, just below the "Logged in as...'' message), you'll see that the list contains messages in all languages, and it is therefore difficult to pull out the messages that are written in just the language that you can read.
A quick solution to this, is to visit each of the forums that you are NOT interested in reading, and click on the "mark all threads as read" link (located top right, just above the list of messages for that forum). This will clear only the messages listed in that forum, from the global list of unread messages.
Now you can revisit the "Unread Messages" list, and you will see unread messages listed only for the forums that you are interested in reading. For me it often halves the size of the list.
It would be nice if that list could be configured to include/exclude your forum choices. Perhaps a feature request for the future?