caustics and dispersion problem again

[simmsimaging]

I have had this in the past but it hasn't come up in a long while, kinda forgot about it.

I cannot seem to get dispersion and photon mapped caustics to happen together. If I activate dispersion the indirectly visible caustics seen inside my refractive material disappear. From what I read on the forums it seems this should work - any tricks I might be missing?


/b