YARV: Yet Another Ruby VM

Having surveyed Ruby Virtual Machine, I found the YARV project. YARV stands for 'Yer another Ruby VM'. Actullay the project was initiated in 2004 by a smart Japanese programmer named SASADA Koichi. The latest version is still 0.4.1, but I think this it the way to go because the current implementation of Ruby is really slow. However, I couldn't find much information on YARV except for a few presentation slides in YARV homepage. Most of discussions have been done in Japanese language. Do we need to learn Japanese to learn Ruby?