On December 2003 SŌ TEN'NENSHOKU AKIRA (総天然色) was published by Kodansha in Japan. This version is a new edition of the previous International Version of AKIRA Colored by Steve Oliff that was also released in Japan by Kodansha from October 1988 to August 1996 in 12 slipcase sets, with English text and a booklet with Japanese translations. This new edition of six volumes was translated back from English to Japanese. Many changes were introduced in the dialogues and the sound effects have been translated too.
I just ordered the first two volumes of this new edition from Amazon japan Marketplace. Each book comes with a transparent plastic slipcase that make them look great but the retail price around $40 for each book is pretty high.
The six volumes available are available in Amazon Japan. In Spain a box set collecting the six volumes and AKIRA CLUB was published available in Amazon Spain. The previous International version is already out of stock but can be find it as second hand books in Amazon Japan Marketplace. In US and Europe the colored version was first published in 38 issues that later got collected as 14 hardcover books, with the last two volumes mostly containing extra artwork and illustrations from the book Akira Club.