asterisk users - Feb 2006 - Direct pickup

I'm trying direct pickup feature but it doesn't work.
Wiki says:
"Directed pickup, this allows you to pickup a call at a specific extension,
maybe you're in another office and you hear a phone ringing and wonder if
it's yours. You dial the pickup number and your extension, and the call will
only transfer if it is your extension."

Instead group call pickup (*8) works.

Any help?


Mimmus