If you have the JAM (Japhar Addon Manager) installed in the image you use, install with it the Password Clearing/Removing plugin that will remove your password (password = nothing/empty).
In this situation, you will need to reflash a new image into the box, as the only way would be to have an HardDisk in the box with the right script, use an external Addon Manager to download a script of removal of password or use the Tux tool (like Norton Commander) that is often preinstalled on the Gemini images.
Yes admin.. Tuxbox tool works fine to recover dreambox root password...i just followed as suggested by u... With tuxbox tool i did not need to reinstaal fresh image... It made me able to solve my forgotten pass easily... Thubs up.... God bless u