ISIPSubscription Create(
	SIPEventType eventType,
	string phoneNumber = ""
)

Function Create ( 
	eventType As SIPEventType,
	Optional phoneNumber As String = ""
) As ISIPSubscription

ISIPSubscription^ Create(
	SIPEventType eventType, 
	String^ phoneNumber = L""
)

abstract Create : 
        eventType : SIPEventType * 
        ?phoneNumber : string 
(* Defaults:
        let _phoneNumber = defaultArg phoneNumber ""
*)
-> ISIPSubscription