BerryBlocker:
Block certain numbers from calling you. (Cost $$)

Download Here

This Program Requires WAP Setup:
(if you have T-Mobile go to BBerry Settings, then 'Advanced Options' then click on TCP, then write this in the APN "wap.voicestream.com")
(if you have Cingular I'm not so sure it depends on your plan but go to the TCP settings and try one of these two options in the APN "isp.cingular" or "wap.cingular")
If these aren't working for you please click here for a more detailed description of how to setup WAP.