“Call Firewall and SMS Blocker” for WM5/WM6 Pocket PC & SmartPhone, basically rejects unwanted calls.

Features:

a. Accecpt all calls – pretty self explainatory
b. Accept call from My Contacts only – accepts calls from contacts only, others are rejected
c. Reject all calls – pretty self explainatory
d. White List – accepts calls only from the white listed nos
e. Black List – accepts all call except from the black listed nos f. Black List Pattern – any no STARTING from the black list pattern list is rejected. for eg. if you enter “123”, so all nos STARTING from “123” will be rejected this is a very nice option with which you can block nos from any particular network, country, city , area or whatever you can think of.
f. There is also an option to reply with an SMS.

Changes:

1. Selective Call Barring.
Now you can restrict selected outgoing calls.
2. Add outgoing calls as Appointments.

http://www.logic-unlimited.com/callfirewall.php