The US version is available on line. I put a link to it over in the forum for Sunshine movie - go check it out.
Only problem is no real shot of Sanada as Kaneda. One person has told me she thinks she sees him at around the 1:12 point in the 2+ minute trailer. I'm going to watch yet again and see if I can catch a glimpse of him!
Also found a link to the UK version. Its easier to find Hiro in this one.
Here it is: http://uk.movies.yahoo.com//features/sunshine.html
And even better news, according to the administrator for the official Sunshine site (www.sunshinedna.com), the trailer for Japan will feature Hiro's voice. I imagine something similar to the US version which uses Cillian's voice.
That version is not finished but as soon as it does appear, I'll put the link here.