I have my cisco cme version of IOS is 12.4(24)T
i have three fxo port and i have connected them to ip phone with connection plar opx 300
my ip phone has two DN 301 and 300
i configured voice-port with connection plar opx 300 and the other voice-port with connection plar 301
when some one calls to one of my line number of FXO port , the ip phone will ring and shows the caller id
but the problem is when the first line is busy and some one call to the other port of FXO the ip phone will ring but no caller id!!!
it shows external and unknown number.
the caller-id enable is under both voice-ports