If you are running P103 or higher, you can reset it through the console connection after you power off and on. You will reset it to factory default, erasing the entire config including the password, but not the IP address. This is done through the bootup menu from the console.
If you have lower than P103, then you will need to contact Quintum directly to have the password reset.
MikeM
mike_voip@hotmail.com