How to change Dreambox password manuel using telnet

press Start menu
press Run
write: telnet your.dream.box.ip (press enter)
Now the telnet consol starts.
write user name: root  (press enter)
write: passwd  (press enter)
write the password you want (press enter)
write your new password again (press enter)

It should look something like this.
It depends on what software and box you are using.
opendreambox 2.0.0 dm7020hd

dm7020hd login: root
root@dm7020hd:~# passwd
Changing password for root
Enter the new password (minimum of 5, maximum of 8 characters)
Please use a combination of upper and lower case letters and numbers.
New password:********
Re-enter new password:********
passwd: password changed.
root@dm7020hd:~#