No I didn't know that.
Here is my configure command when I install Codeblocks.
./configure --prefix=`echo ~`/Codeblocks/ --with-contrib-plugins="all,-spellchecker,-BrowseTracker,-FileManager,-NassiShneiderman"
I think the plugin you're talking about is compiled too.
When I go in "Settings => Editor" I can see the "Occurences Highlight" part. And all checkbox are checked, and the "minimum selected length" is set to 3.
I can't figure out why it's not working here.
I'll make an update and see if it fix it.
EDIT: I confirm it works again in svn 9903, thanks jens