The phone has a Factory Reset option but it's accessible only from the Settings menu and since you cannot access the phone, it's impossible to use it. According to the web information, the phone lacks recovery mode but you can try it for yourself. Keep Power Up + Power (and sometimes Menu button) until you enter Recovery. If it works, you can use Wipe Data to factory reset the phone and remove any settings and passwords.
Another solution is to take the phone to a local phone repair shop and it will be resat for a very small fee.