Calling-Us Professional is the unified messaging solution for highest claims. ISDN hardware must support CAPI. Here is a list of some features: Answering equipment, message request, Voice-to-eMail, PC-Telephone, Call forwarding, Callback, Callthrough, Serial-voice-messages, Serial fax, Fax polling server, Fax-to-eMail, Fax-forwarding, Fax-notifications, Serial-SMS-messages, SMS-notifications, eMail-To-SMS, DTMF/Speech-supported navigation, Connection, Switching, eMail-forwarding, eMail-To-Fax, eMail-To-Voice, eMail-notifications, VIP-welcome, Web-info, Eurofile-data server, Caller identification.