Sega accidentally uploads old build of Sonic 4 on JP Wiiware.

Interesting discovery by Evilhamwizard over at Sonicretro:

"Sega accidentally uploaded an OLDER build of Sonic 4 on Wiiware over in Japan. The build got leaked before they had the chance to upload the new one, but if you want to check it out you need to get the file under the release name "ps-wsnj". I tried looking for it for days, but the only way I was able to find a working download was on Usenet. It was on some file upload sites but they got pulled as far as I could tell. So you're going to have to do some work to find it (maybe)."

For more info on the differences check his post here: http://forums.sonicretro.org/index.php?s=8219d0e8d26a789ab44cad49a67b5c81&showtopic=23001&st=1815&p=542731&#entry542731