asterisk users - Aug 2008 - Caller ID in IAX trunk, SIP trunk, between extensions and from FXO

Hi All;

If I need to see on my Polycom LCD the caller id of the other caller extension
(for example, if 801 called the polycom of 802 then how can I let the LCD of
polycom of the extension 802 to display the 801 as caller)? My polycom model is
330.

Also, I have IAX trunk between two Asterisk boxes, in the beginning I was able
to see the telephone number on the Polycom 330 LCD of the caller number from
other Asterisk, (I was able to see the mobile number that was calling to
Asterisk Box A and enter the extension of the Polycom that is registered with
Asterisk Box B), but now, I am not able. So what the missing configuration that
might cause this problem?