1. From the home screen, tap Messaging.
   
2. Press the Menu key.
   
3. Tap Settings.
   
4. Scroll to "Spam message settings", then tap Register number as spam.
   
5. Tap Create.
   
6. Enter the desired phone number, then tap Save.
   
7. To remove a number from the block list, touch and hold the desired number.
   
8. Tap Delete.
   
9. Tap OK.