JAL Mileage Bank - Upgrade Certificate

JAL's web says that JMB Diamonds get
"8 Upgrade Certificates for International and Japan Domestic flights*2"
"*2 For Upgrade Certificates, two certificates are required per international sector to upgrade the class of service..."

Does it mean "2 certs for an entire roundtrip" or "2 certs for each way" or "2 certs for each segment"?

2certs for 1 segment/each way. 2005's 8certs for total 4 segments.

and,
JMB rules has changed(effective Apr/06~).　JMB diamond member receives 4 international-upgrade certs instead of 2005's 8certs and the one cert is limited to one segment. You cannot use them to upgrade domestic flight. JMB diamond member also gets 14 domestic-upgrade certs instead of 2005's 6certs. Those 2006 certs are valid through Mar/31st/07.

Just checked JAL web-site(English version) though...It has yet to be revised.
http://www.jal.co.jp/en/jalmile/flyon/status.html

Call JAL..You'll find out.

-Upgrading rule is subject to change without prior notice- :p