A method and apparatus for processing an incoming call over a telephone line in a computer system, wherein a telephone manager program passes the telephone line to a telephony application program according to at least one user option, a set of user preferences, and DTMF or calling tones....http://www.google.de/patents/US5471522?utm_source=gb-gplus-sharePatent US5471522 - Telephone line sharing for a personal computer system
Telephone line sharing for a personal computer system
