Last year I was quite successful using hydrogen peroxide to scarify the seed coat. I soaked the seeds for 4 hours in regular peroxide then rinsed them a couple times. I stored them in the fridge for 90 days in a ziplock within a damp paper towel. Sowed them in pots and many of them started sprouting in a couple months after that. I've read you can also use a diluted bleach solution to scarify the seed also.