I modified the docky "Trans Theme" by Akshat Jain http://gnome-look.org/content/show.php/Trans+Theme+for+Docky?content=117701, I simply removed the borders on the background picture...it is now completely transparent.
| Install :
Copy the extracted folder in :
| Acknowledgment :
Akshat Jain for the theme.
Alecive for the awoken icons I used on the screenshot : http://fav.me/d2pdw32
| License :
Creative Commons BY-SA
(the presentation picture is under Creative Commons BY-NC-ND)