The Samsung SGHA877 (as well as many other 3G phones) have the capability to "Block Caller."   This feature is not dependant on any service that your carrier might provide or offer.  It simply ignores calls from any number you add to the reject list.  I'm glad to have found out who the a-holes are.  They wouldn't even tell me who they were before they started asking me who I am so they ended up on my reject list.  TO anyone WHO MAKES THESE CALLS FOR A LIVING THAT MAY BE reading this, WE HAVE A RIGHT TO KNOW WHO YOU ARE BEFORE WE TELL YOU WHO WE ARE - YOU CALLED US, REMEMBER?

doesn't leave message, just constantly calls.

i'm receiving calls from this number daily. they don't leave a message. my number is on the do-not-call list. what should i do?

Same here... I just put the number on the reject list so it doesn't even ring  when they call & they don't leave msg

Got a call from this number, they never leave a message.  How do I block this number?