Actually, it's not all that crazy. Put the cell phone numbers in the field reserved for the pager numbers. Use the Public-Unknown-Numbering table to assign a unique 10-digit phone number to your phantom extension that is assigned to your Crisis Alert setup (I use 911-911-0911).
Answered crisis alert calls will hear the beep beep beep of the additional pager digits, but they can be ignored. It's the actual notification call that's important. Of course, you're still limited to three pager/cell notification, which stinks.
Susan
Muffins are just ugly cupcakes.