Umm... you can default the database directly through the front panel menu...
Press center button, arrow down to System Menu, press center button, arrow down to Default Database, press center button and follow prompts.
Remember this will only clear the database, NOT the licensing... the licensing is tied to the compact flash card and cannot be changed except by a certified technician with access to Mitel AMC.
This will gain you a dumb system... that's it.