Hajimu UMEMOTO 5818927a00 Try to guess prefixlen for guessable cases.
- /0 if matches ::/128
- /64 if matches 2000::/3 and lowermost 64 bit is all 0
- /128 if matches 2000::/3 and lowermost 64 bit is non-zero 0

Obtained from:	KAME/NetBSD
2002-05-20 15:01:19 +00:00
..