Bouncy Castle BC 1.54 - 1.59, BC-FJA 1.0.0, BC-FJA 1.0.1 and earlier have a flaw in the Low-level interface to RSA key pair generator, specifically RSA Key Pairs generated in low-level API with added certainty may have less M-R tests than expected. This appears to be fixed in versions BC 1.60 beta 4 and later, BC-FJA 1.0.2 and later.