We have new phones at work. They are VOIP phones. We have a few different locations around town. Each building has an overhead page feature in the phone system. At one building, I was bored, and while messing about with the phone, I realized that when you hit the "page" button, it rings for a brief moment, and then pages. I soon figured out what the 4 digit extention for the overhead page was, and by placing the the same three digit suffix the incoming phone lines had, I was soon able to use the overhead page from my cellphone (and from Japan a few weeks later). Recently transsfered to another location, I attempted to try it again. However, the internal overhead page number here is 5 digits. This has me rather confused. How can I figure out how to access the overhead page feature from an outside line? We have am internal phone system between all of our locations that allows us to call one another by simply dialing the last 4 digits, and I have found that dialing these 5 digits from another one of or buildings will acces the paging system, but I would really like to be able to do it from my cellphone.
Usually, I enjoy figuring this kind of stuff out on my own, but I'm a little lost here.
Here's what our new phones look like: