In r6574 no longer default (with projection camera it didn't work so well), but can be set with ISceneManager::setTransparentNodeSorting(irr::scene::ETNS_PLANE_CENTER);
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Fixed in svn trunk r6573, will be in Irrlicht 1.9
In r6574 no longer default (with projection camera it didn't work so well), but can be set with ISceneManager::setTransparentNodeSorting(irr::scene::ETNS_PLANE_CENTER);