I would imagine if you had the freebase, which does not crystallize and remains oil, could be vaporized if a low temperature was used. I'd love to see some freebase MDMA infused cannabis to throw through a digital volcano.....
That being said I don't think there would be many who can access the freebase MDMA. One could probably basify the MDMA HCl to leave freebase MDMA and proceed to either vaporize the MDMA oil, which would be hard to measure at those doses. If one infused it into herb as one does with dmt for changa it could work beautifully. One day I hope to try and I keep eye out for reports of such, but as of yet I haven't found much info.