How to block a number

[GoldenMerc]

Well i know how to do it with my G1, but my friend keeps getting abusive calls from a number and i was thinking is there a easier way than calling them and getting the number blocked?
+Rep for help, i dont know her fone so pleaseee dont ask.
Ross

[syko2006]

Get her to call phone provider and say I would like to put a block on this number please, thanks.

They should be able to do it. :)