In essence Caller ID ETSI and FSK US (Bellcore) is based on the same pattern as;
_____________ ___________________ _________ ________________ _____________
|First Ring burst |_500ms_|Channel seizure 300 bits|__|Mark Signal|__| Caller ID Message|_200 ms_|Second ring burst |
So basically any kind of device should be work without any problem, unfortunately during these process if some noises (as miss ground connection or others) happens during the process can make failed to process caller-id information, by the modem.
Mc GRATH Ricardo