Last modified: 2010-05-15 15:37:49 UTC
When customizing the sidebar in 1.5beta3 by editing MediaWiki:Sidebar, the newly added link is surrounded by < and > (HTML entities < and > respectively). Example: Add '**Test|Test' to the bottom of the list. Result: <Test> which links to: 'http://<wikiURL>/-- error:_link_target_missing--'.
You have to create MediaWiki:Test and put something in it first.