Page()?

I’ve seen in the release notes for asterisk 1.2.0-beta2 that Page() has been added (voip-info.org/wiki-Asterisk+ … d+Intercom). I have asterisk 1.2.1 installed from source, but when I try to use the Page() command, I get:

No application ‘Page’ for extension (internal, 100, 2)

What gives?

Thanks,
Ken