As far as I remember (haven't kept up with new Unity features), you have to physically program each extension you want callers to reach as either a full voicemail (or UM) subscriber, a call handler or an internet subscriber. This is the only way a caller can reach an extension at the main autoattendant prompt.

There is an after greeting action that you can configure that allows users to enter any extension they wish (Send call handler to Caller System Transfer).

http://www.cisco.com/en/US/products/sw/voicesw/ps2237/products_administration_guide_chapter09186a008022d1ca.html#wp1056790

This option will at least allow you to say, "if you want to reach a conference call, press 2" when they press 2, they hear "enter the extension you wish to reach.

Personally, I would use either a call handler or an internet subscriber for the extension itself. If you are networking Unity servers, remember that call handlers are not distributed across servers (or at least they weren't) whereas Internet subscribers are. There are more differences that you will have to be aware of, i.e. you can assign a call handler to a subscriber so they can administer the greetings.

We are seriously reconsidering removing our autoattendant role from Unity and moving it to IPCC. Two great advantages are you don't have to program each extension, and off-campus call identification is maintained (double rings and ring no-answer/busy targets are honoured).

Lelio

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