The call data field is used to provide additional information related to a call in TAPI. Some systems, for example Avaya Voicemail Pro, use this field to pass additional information to TAPI applications monitoring the calls. New TapiCallCallData property gives the application access to the call data. The CallData flag has been added to the TapiCallInfoState enumeration. AddTapi.NET fires the TapiAppCallInfo event with this flag set when the call data becomes available or changes.

Special information tones such as Reorder, Intercept or No Circuit indicate that an outgoing call has failed. AddTapi.NET 5.2 can detect and report special information tones to the application when running on telephony hardware with SIT detection capabilities such as Way2Call Hi-Phone. When a SIT is detected the call transitions to the SpecialInfo state and then disconnects. AddTapi sets the TapiCallDisconnectMode property based on the type of SIT that was detected.

New version adds TapiCallCallDuration property that contains duration of the call. Call duration is calculated from the moment the call transitions to the Connected state.

In previous versions of AddTapi.NET the application could miss a call state transition if TapiAppCallState events were firing quickly one after another. Version 5.2 processes call state messages from TAPI more efficiently and ensures that the TapiCallState reported to the application in the TapiAppCallState event handler matches call state in the corresponding TAPI message.

- Added TapiAddressAddressFeatures property that describes the operations that can be invoked on the address.

- Added CallID and RelatedCallID flags to the TapiCallInfoState enumeration. These flags indicate that the TapiCallCallID or TapiCallRelatedCallID property has changed in the TapiAppCallInfo event.

- Fixed: Some incoming calls where reported as outgoing on HiPath TAPI 170.

- Fixed: Non-directed TapiCallPark(String) could time out on some systems.