HELP – Locked out of my Fujitsu Siemens S7110 WB2 Lifebook!

I lend my Fujitsu Siemens S7110 WB2 Lifebook to a client of mine and now its locked and I can’t get in! I have backups of everything I store on the laptop so I am happy wiping it if that will let me use it. I now comes up asking for a User Authentication with an Authentication type of ASCII Password. This was never on it when I gave them – not very good with passwords 🙁 and as I lend it out it would just be too much hassle. Can anyone help me with this as it is vital to teaching as I need a portable computer.