I'm using the unity 4.2 integrating with CUCM.
Create the call handler for Auto Attendant.In the CCM side we configured the CTI RP forwarded to the VMAIL call handler.
When we dialed the AA number ,we got the welcome greetings , when the moment we dial the desired ext call transfered to that extension voice mail.
We checked the call transfer option @ the subscriber options , but the behaviour is same call transfered to desired extension voice mail only.
We enabled the call transfer for the subscriber template also.