TAPI how to distinguish between incoming and outgoing call

Hi,

I am looking for a way to check if handled tapi event is related with outgoing call. My event handling method looks like this:

privatevoid tapi_ITTAPIEventNotification_Event(TAPI_EVENT TapiEvent,object e)
{....}

What is the reliable way for checking if event is related to outgoing or incoming call?

thanks

bartek