Stacked particles transparency

Hi,
We have a probleme here with particles not resolving correctly the transparency when they are stacked on Z, using a renderer 3d.
If the particle has a long alpha ramp i get a result like on the screenshoot...
I can't find the right setting to activate a full additive mode on the particle, just like on OPENGL or on particular on AE
We have a probleme here with particles not resolving correctly the transparency when they are stacked on Z, using a renderer 3d.
If the particle has a long alpha ramp i get a result like on the screenshoot...
I can't find the right setting to activate a full additive mode on the particle, just like on OPENGL or on particular on AE