This is a mediawiki extension, which resolves the authentication part (0023328)

MantisBT User will be automatically authenticated against mediawiki
The mediawiki session will be shared with mantisBT-Session, so you can also use full functionality of MantisBT within mediawiki-extensions (eg mantisbt-reports, mantisbt-forms for new tickets, graphical summaries)

1. install extension in mediawiki/extensions/Auth_MantisBT

2. create a file in mantisbt/config/ with all global variables definition included (config/global_vars.php)
   sample global_vars.php is included in extension Archiv

3. for this extension to work, you also need to enhance session_id on MantisBT side to match minimum of 32 characters
   sample implementaion is included in extension Archiv