I was recently doing a Lync deployment for a customer and they had some very complex Auto Attendant requirements so we decided to use "Interactive Response Groups". The IRG's really are a nice feature, you can specify up to two levels of questions that callers will hear and each question can have up to four possible answers.

So the issue, an IRG can only send calls to a Response Group Queue and normally this doesn't cause problems since our call paths tend to be sending to users. But, every company needs a Staff Directory, is deploying Exchange UM and wants to take advantage of 

I have a working configuration now with this Interactive Response Group in Response position "4", set to send to the AA-Staff-Directory Queue. I then created a group called AA-Staff-Directory and made it a member of the Queue and added the reception user to it.

Adding a user to the group, and adding the group to the Queue is very important. This user will never get called but you cannot skip this step.

Now click the check-box "Enable Queue Overflow", set the "Maximum number of calls" to 0, set the "Call Action" to "Forward to SIP Address" and then enter the SIP address of your auto attendant. Make sure you have set it up with OCSUMutil.exe