No, this isn't currently supported. However, I will add it to the list to investigate for a future release. You would need to do a template override for our mod_jfbcsocialshare/tmpl/default.php file to add this functionality.
We're glad to hear that the override will work for you. The idea is a good one, it will just take some time to investigate the best way to do it in a way that would work across all sites.
Social Share button for email mailto ?
