Mentions in Twitter do not work

Twitter changed the @-replies to mentions. Therefore everytime someone writes anywhere in a tweet @testuser, testuser will see it in his @-replies. This should work with any twitter-client OOB. In my experience it worked with at least 2 twitter-clients out of the box.
Mentions that do not start with a @testuser won't show in Eventbox in the @-replies.
See also: http://blog.twitter.com/2009/03/repli... for this