We’ve now ported the j2mantis plugin to Joomla 1.6. So it is possible to show and add Bugs with your Joomla 1.6 CMS System to Mantisbt.
For Joomla you need to have installed our Recaptchup Plugin.
You can download j2Mantis 0.4.0 J1.6 here.
A version with some bugfixes is also available for Joomla 1.5. j2Mantis 0.3.3 J1.5 download
Whether we will support Joomla 1.5 in the future is not yet clear, since we are porting our installations to Joomla 1.6.
So consider porting to Joomla 1.6 as well.