"arc4random implementations in FreeBSD and NetBSD aren't quite state of the art anymore" NetBSD's has been updated, now uses chacha20 and fixes the other issues (duplicated random number state on fork for example).
http://www.openbsd.org/cgi-bin/man.cgi?query=arc4random&apro...
https://github.com/delphij/freebsd/compare/master...featuref...