Irrlicht 1.5.2 is out, it's mainly a bug fix release. To repeat what I just wrote on the
Irrlicht website:
We just released an update to the 1.5 branch of the Irrlicht engine, version 1.5.2. It contains several updates and bugfixes, related to terrain smoothing, joystick support, OS/XCode updates and MS3D loader fixes. Happy downloading!