SET FULL TRANSPARENT PANEL IN UBUNTU 9.10

1. Go to Applications (or Main Menu) > Accessories > Terminal.
2. Enter cp -R /usr/share/themes/Ambiance ~/.themes/
3. Enter gedit ~/.themes/Ambiance/gtk-2.0/gtkrc to open Ambiance's ftkrc file with gedit.
4. Search for this line bg_pixmap[NORMAL] = "panel_bg.png"
5. Comment out the line by placing a # at the beginning of the line, like this: # bg_pixmap[NORMAL] = "panel_bg.png"
6. Save the gtkrc file.
7. Go to System > Preferences > Appearance, switch to the other theme and then back to the Ambiance theme.

Note: If you'd like to change to the Radiance theme, replace Ambiance with Radiance in the above command lines, but you'd like to change to the New Wave theme, then enter cp -R /usr/share/themes/"New Wave" ~/.themes/ in step 2, enter gedit ~/.themes/"New Wave"/gtk-2.0/gtkrc in step 3, search for and comment out this line bg_pixmap[NORMAL] = "Images/Panel/PanelBarLong.png" in steps 4 and 5 respectively.