3 files changed, 14 insertions, 9 deletions
diff --git a/SocketHttpListener.Portable/Net/HttpConnection.cs b/SocketHttpListener.Portable/Net/HttpConnection.cs
index 8e472117e..67dd5c958 100644
--- a/SocketHttpListener.Portable/Net/HttpConnection.cs
+++ b/SocketHttpListener.Portable/Net/HttpConnection.cs
@@ -204,12 +204,12 @@ namespace SocketHttpListener.Net
             return i_stream;
         }
 
-        public Stream GetResponseStream()
+        public Stream GetResponseStream(HttpListenerRequest request)
         {
             // TODO: can we get this stream before reading the input?
             if (o_stream == null)
             {
-                if (context.Response.SendChunked)
+                if (context.Response.SendChunked || request == null || request.HasExpect100Continue)
                 {
                     o_stream = new ResponseStream(stream, context.Response, _memoryStreamFactory, _textEncoding);
                 }
@@ -490,7 +490,7 @@ namespace SocketHttpListener.Net
             {
                 if (!context.Request.IsWebSocketRequest || force_close)
                 {
-                    Stream st = GetResponseStream();
+                    Stream st = GetResponseStream(context.Request);
                     if (st != null)
                         st.Dispose();
 
diff --git a/SocketHttpListener.Portable/Net/HttpListenerRequest.cs b/SocketHttpListener.Portable/Net/HttpListenerRequest.cs
index 5631fc0a1..767f1c542 100644
--- a/SocketHttpListener.Portable/Net/HttpListenerRequest.cs
+++ b/SocketHttpListener.Portable/Net/HttpListenerRequest.cs
@@ -179,16 +179,21 @@ namespace SocketHttpListener.Net
                 }
             }
 
-            if (String.Compare(Headers["Expect"], "100-continue", StringComparison.OrdinalIgnoreCase) == 0)
+            if (HasExpect100Continue)
             {
-                var output = context.Connection.GetResponseStream();
-                
+                var output = (ResponseStream)context.Connection.GetResponseStream(this);
+
                 var _100continue = _textEncoding.GetASCIIEncoding().GetBytes("HTTP/1.1 100 Continue\r\n\r\n");
 
-                //output.InternalWrite(_100continue, 0, _100continue.Length);
+                output.InternalWrite(_100continue, 0, _100continue.Length);
             }
         }
 
+        public bool HasExpect100Continue
+        {
+            get { return String.Compare(Headers["Expect"], "100-continue", StringComparison.OrdinalIgnoreCase) == 0; }
+        }
+
         static bool MaybeUri(string s)
         {
             int p = s.IndexOf(':');
diff --git a/SocketHttpListener.Portable/Net/HttpListenerResponse.cs b/SocketHttpListener.Portable/Net/HttpListenerResponse.cs
index 93358cae4..8c610d725 100644
--- a/SocketHttpListener.Portable/Net/HttpListenerResponse.cs
+++ b/SocketHttpListener.Portable/Net/HttpListenerResponse.cs
@@ -149,7 +149,7 @@ namespace SocketHttpListener.Net
             get
             {
                 if (output_stream == null)
-                    output_stream = context.Connection.GetResponseStream();
+                    output_stream = context.Connection.GetResponseStream(context.Request);
                 return output_stream;
             }
         }
@@ -489,7 +489,7 @@ namespace SocketHttpListener.Net
 
             int preamble = encoding.GetPreamble().Length;
             if (output_stream == null)
-                output_stream = context.Connection.GetResponseStream();
+                output_stream = context.Connection.GetResponseStream(context.Request);
 
             /* Assumes that the ms was at position 0 */
             ms.Position = preamble;