Is it possible to clear the internal memory of the Nokia E-50?

[decemberfox]

I just got a Nokia E-50 phone (the one with the camera) second hand off my dad's work. Problem is, it's got like 100 contacts and I really don't want to manually delete them all. Is there a way that I can reset the internal memory so that it's like new?

I don't have a memory card if that matters.