Hi Guys:
Equinox3d is a powerful linux 3d modeler that is becoming more and more pro with each release. There have been two releases lately: 0.86 and 0.87.
check its latest features here:
http://www.equinox3d.com/News.html
As you can see, it fully supports the COLLADA format and it's also starting to use lightmaps, making it an interesting alternative for Irrlicht since COLLADA exports everything: geometry, cameras, lights, textures and I guess lightmaps.
It could be the all-around-modeler we dream of for Irrlicht.