How To Unlock Handspring:
Model: Treo 180 & 270
1. Switch ON your phone without SIM Card
2. Enter *#*#Unlock Code#
Model: Treo 600 (Unlock method 1)
1. Insert an authorized Sim Card and turn ON your phone
2. Menu and select "Phone Tool" or "Phone Application
3. Enter on Virtual Keyboard *#*#Unlock Code#
Model: Treo 600 (Unlock method 2)
1. Insert an unauthorized Sim Card and turn ON your phone
2. Enter the Unlock Code