3Com VCX V7122 User Manual page 256

14 "We are unable to complete your call".
15 "Transferring your call".
16 "Thank you for using the calling card service".
17 "The menu is currently empty".
18 "Operator assistance is currently unavailable".
19 "You are unauthorized to access the number you are attempting to call".
20 Final alert (one beep at 640 Hz for 0.5 second duration).
21 Time of call expired (one beep at 640 Hz for 1.5 second duration).
256 3Com VCX V7122 SIP VoIP Gateway User Manual