I finished my work who was based on the ColladaMax exporter . I modified the ColladaMax exporter in a way that now the smoothing groups informations are also exported in the dae file !
I have to clean up a bit the code and fix the 2 errors I have with the coherency test and it will be ok.
To do that work I used ColladaDom instead of FCollada. (I don't know why but i feel really better with the DOM than FCollada)
this is a screenshot of what a dae with smoothing group looks like :
If this project interest someone let me know ^^