I have been walking the internet and found some movies about his new song 野に咲く花のように (roughly translated as : Like the flower that blooms in the field *a few posts up I gave you a link to the song*)
Here is a short interview:
http://www.oricon.co.jp/music/interview/070131_02.html
This is an article about the students graduation and how it is a journey through life. Gackts song, 野に咲く花のように , is link to this. At first I was watching the PV (music clip) with no sound and didnt understand why school students.hahaha. The title of the song expresses "like the flower which blooms in the field without being defeated under any condition, it is strong and would like to bloom".
Oh I found this, this might explain where the song comes from.
*please note, this is a free flow translation, I did not directly translate word for word because I find that it doesnt make sense some times.hahaha*
Gackt was on late night radio when a message from a fan touched his heart.The fan requested that gackt be at their graduation ceremony. More than a year later he turned up and sang the song for them. I hope this has helped. Here is a link for it. If anybody would like to double check that I have translated properly. It is down near the bottom of the page. The first half is just selling the music.
Amazon product ASIN B000LPRL38
Sorry this post is very long