Easy Busy for S60

[wraggster]

Easy Busy from WebGate lets you keep away unwanted callers. Sales calls and phone surveys, stalkers, your ex-boy or girlfriend, your mom (at times), so many calls that you want to avoid... Easy Busy comes to help and allows you to keep away calls from people that you would like to ignore. Calls are rejected by an instant busy tone (not interrupting your privacy) with ultra-fast caller recognition so that the caller thinks the line is busy.

http://my-symbian.com/s60v3/software/applications.php?name=Easy_Busy&fldAuto=721&faq=1