SilkJS includes a lot of libraries that have different licenses. The idea is to allow anyone to download and use SilkJS and live up to those licenses as they see fit.
If you want to sell SilkJS, you have to pay Oracle a license fee because SilkJS uses libmysql.
If you want to sell SilkJS, you have to pay Oracle a license fee because SilkJS uses libmysql.
Make sense?