Hi Prayboy, don't know about South Pacific region but in Europe there is NO specific regulation, only recommendations. I've pasted an extract from the faq section from the official eurocontrol site website below. Hope that's of some use.
http://www.ecacnav.com/RVSM/default.htm
Question P6: What are the Rates of Climb / Rates of Descent to be applied in RVSM airspace when being cleared from one RVSM level to another?
Answer: There is no specific regulation as to the vertical speeds within EUR RVSM airspace. The guidance to prevent over/undershooting and the triggering of TCAS alerts should be followed. It is recommended that a vertical speed of between 500 and 1000 fpm is applied between 1000 and 1500 feet from the Cleared Flight Level (CFL). Therefore, in the absence of a specific ATC instruction with regard to climb rates, a normal climb or descent rate appropriate to the profile should be carried out until approximately 1000 - 1500 ft before the CFL.