Hi Kevin,
Here is the CUE method;
"Announcement Only" Mailbox
You can use either the Cisco Unity Express AA or a voice mailbox in order to play an announcement to callers that changes frequently (perhaps daily or hourly). Cisco Unity Express does not have a direct feature or mailbox type called an "announcement-only" mailbox, but you can use various other Cisco Unity Express features in combination to achieve this operation.
AA Application
The Cisco Unity Express AA is the most flexible way of implementing an "announcement-only" mailbox implementation. Write an AA script that plays an announcement (prompt) to callers. The simple example file (Announcement-mbox.aef) Associate this script with a pilot number (in the same way you would build a Cisco Unity Express AA application). Callers to the pilot number will hear the announcement and the call will be automatically disconnected by the Terminate step.
Voice Mailbox Application
A Cisco Unity Express GDM can also be used to implement an "announcement mailbox" application. Define a GDM, associate it with an extension (which becomes the equivalent of your pilot number for this application), and log in to the GDM and record the announcement you want played as the outgoing greeting of the mailbox. You can record an alternate greeting as well and therefore, by changing the greeting of the mailbox between standard and alternate, you could alternate between two different prerecorded announcements.
From this good CUE doc;
http://www.cisco.com/en/US/products/sw/voicesw/ps5520/products_implementation_design_guide_chapter09186a0080406670.html#wp1015952
Hope this helps!
Rob