Wash the currants and remove them from the panicles with a fork. In a large, tall pot, mix the currants and jam sugar. Cut open the vanilla pod and scrape out the pulp. Halve the pod, break the cinnamon into small pieces.
Add the cinnamon, vanilla pulp and vanilla pod to the pot. Bring to the boil while stirring over high heat, boil for at least 3 minutes until bubbly. If necessary, skim and pour hot into prepared, sterilized glasses, close and place on the lid for approx. 5 minutes.
Turn the glasses over, let them cool down. Store in a cool and dark place.