DraftHybi10Processor.SendHandshake NullReferenceException

[MiloszPawlowski]

NuGet version: 0.15.2
Exception: System.NullReferenceException: Object reference not set to an instance of an object
at WebSocket4Net.Protocol.DraftHybi10Processor.SendHandshake (WebSocket4Net.WebSocket websocket) [0x0021f] in <4cb06ef85758
Stacktrace:
DraftHybi10Processor.SendHandshake (WebSocket4Net.WebSocket websocket)
WebSocket.OnConnected ()
WebSocket.client_Connected (System.Object sender, System.EventArgs e)
ClientSession.OnConnected ()
AuthenticatedStreamTcpSession.OnAuthenticatedStreamConnected (System.Net.Security.AuthenticatedStream stream)
SslStreamTcpSession+d__1.MoveNext ()
AsyncMethodBuilderCore+<>c.b__6_1 (System.Object state)
QueueUserWorkItemCallback.WaitCallback_Context (System.Object state)
ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx)
ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx)
IThreadPoolWorkItem.ExecuteWorkItem ()
ThreadPoolWorkQueue.Dispatch ()
_ThreadPoolWaitCallback.PerformWaitCallback ()