I finally found some images which really took LOOOONG to load (or better, to create the scene node) so I implemented the per-material mesh buffer approach initially mentioned by myself in this thread. Now, loading is quite fast even with lots of faces (it was the bounding box calculation performed for each face
Also fixed some material and normals problems, moved the normal calculation into the parser (so normals are calculated only once now) and probably some other good things
Ah, another change to Irrlicht headers: The subString method in irrString.h must be declared const (for the same reason as toEuler)