I always have a hard time with terminology.

When you "Page" someone, this is usually done thru an external paging horn like in a warehouse.
Internal paging (one way)comes thru the telephones speaker as a beep and then voice announcement, not a ring.

If you are calling an individual station, that is an intercom call and you can change the ring tone on the intercom button. This would not affect the ringing for trunk calls.

Now available Voicemail Programmer Kit to program your Toshiba Voice Mail across your network.

Toshiba Technical Support at: One Ring Telecom