Asterisk "caller ID"


Hi everybody…i have a problem on the VoIP phone…i connected 3 pbx by voip trunks…when i call a internal phone i see the caller ID but when i call an external phone (other pbx) i don’t see the caller ID…but i see only, on two lines, on the phone “asterisk” and “asterisk” (the model of the phones is “Grandstream gxp2000”)…i try to insert “caller ID” on the each trunk but i don’t see the number…

Some ideas? thanks… :smile: