diff --git a/websocket-sharp/Net/ClientSslAuthConfiguration.cs b/websocket-sharp/Net/ClientSslAuthConfiguration.cs
index c8f13d6a..5e71bf88 100644
--- a/websocket-sharp/Net/ClientSslAuthConfiguration.cs
+++ b/websocket-sharp/Net/ClientSslAuthConfiguration.cs
@@ -47,6 +47,11 @@ namespace WebSocketSharp.Net
   {
     #region Private Fields
 
+    private X509CertificateCollection           _certs;
+    private LocalCertificateSelectionCallback   _certSelectionCallback;
+    private bool                                _checkCertRevocation;
+    private SslProtocols                        _enabledProtocols;
+    private string                              _host;
     private RemoteCertificateValidationCallback _serverCertValidationCallback;
 
     #endregion
@@ -92,10 +97,10 @@ namespace WebSocketSharp.Net
       SslProtocols enabledSslProtocols,
       bool checkCertificateRevocation)
     {
-      TargetHost = targetHost;
-      ClientCertificates = clientCertificates;
-      EnabledSslProtocols = enabledSslProtocols;
-      CheckCertificateRevocation = checkCertificateRevocation;
+      _host = targetHost;
+      _certs = clientCertificates;
+      _enabledProtocols = enabledSslProtocols;
+      _checkCertRevocation = checkCertificateRevocation;
     }
 
     #endregion
@@ -109,7 +114,15 @@ namespace WebSocketSharp.Net
     /// <value>
     /// <c>true</c> if the certificate revocation list is checked; otherwise, <c>false</c>.
     /// </value>
-    public bool CheckCertificateRevocation { get; set; }
+    public bool CheckCertificateRevocation {
+      get {
+        return _checkCertRevocation;
+      }
+
+      set {
+        _checkCertRevocation = value;
+      }
+    }
 
     /// <summary>
     /// Gets or sets the collection that contains client certificates.
@@ -117,7 +130,39 @@ namespace WebSocketSharp.Net
     /// <value>
     /// A <see cref="X509CertificateCollection"/> that contains client certificates.
     /// </value>
-    public X509CertificateCollection ClientCertificates { get; set; }
+    public X509CertificateCollection ClientCertificates {
+      get {
+        return _certs;
+      }
+
+      set {
+        _certs = value;
+      }
+    }
+
+    /// <summary>
+    /// Gets or sets the callback used to select a client certificate to supply to the server.
+    /// </summary>
+    /// <remarks>
+    /// If this callback returns <see langword="null"/>, no client certificate will be supplied.
+    /// </remarks>
+    /// <value>
+    /// A <see cref="LocalCertificateSelectionCallback"/> delegate that references the method
+    /// used to select the client certificate. The default value is a function that only returns
+    /// <see langword="null"/>.
+    /// </value>
+    public LocalCertificateSelectionCallback ClientCertificateSelectionCallback {
+      get {
+        return _certSelectionCallback ??
+               (_certSelectionCallback =
+                 (sender, targetHost, localCertificates, remoteCertificate, acceptableIssuers) =>
+                   null);
+      }
+
+      set {
+        _certSelectionCallback = value;
+      }
+    }
 
     /// <summary>
     /// Gets or sets the SSL protocols used for authentication.
@@ -126,11 +171,22 @@ namespace WebSocketSharp.Net
     /// The <see cref="SslProtocols"/> enum value that represents the protocols used for
     /// authentication.
     /// </value>
-    public SslProtocols EnabledSslProtocols { get; set; }
+    public SslProtocols EnabledSslProtocols {
+      get {
+        return _enabledProtocols;
+      }
+
+      set {
+        _enabledProtocols = value;
+      }
+    }
 
     /// <summary>
     /// Gets or sets the callback used to validate the certificate supplied by the server.
     /// </summary>
+    /// <remarks>
+    /// If this callback returns <c>true</c>, the server certificate will be valid.
+    /// </remarks>
     /// <value>
     /// A <see cref="RemoteCertificateValidationCallback"/> delegate that references the method
     /// used to validate the server certificate. The default value is a function that only returns
@@ -155,7 +211,15 @@ namespace WebSocketSharp.Net
     /// A <see cref="string"/> that represents the name of the server that shares
     /// a secure connection.
     /// </value>
-    public string TargetHost { get; set; }
+    public string TargetHost {
+      get {
+        return _host;
+      }
+
+      set {
+        _host = value;
+      }
+    }
 
     #endregion
   }
diff --git a/websocket-sharp/WebSocket.cs b/websocket-sharp/WebSocket.cs
index 611c19d5..b37cfe7f 100644
--- a/websocket-sharp/WebSocket.cs
+++ b/websocket-sharp/WebSocket.cs
@@ -70,8 +70,6 @@ namespace WebSocketSharp
 
     private AuthenticationChallenge _authChallenge;
     private string                  _base64Key;
-    private LocalCertificateSelectionCallback
-                                    _certSelectionCallback;
     private bool                    _client;
     private Action                  _closeContext;
     private CompressionMethod       _compression;
@@ -234,40 +232,6 @@ namespace WebSocketSharp
 
     #region Public Properties
 
-    /// <summary>
-    /// Gets or sets the callback used to select a client certificate to supply to the server.
-    /// </summary>
-    /// <remarks>
-    /// If the value of this property is <see langword="null"/>, no client certificate will be
-    /// supplied.
-    /// </remarks>
-    /// <value>
-    /// A <see cref="LocalCertificateSelectionCallback"/> delegate that references the method
-    /// used to select the client certificate. The default value is <see langword="null"/>.
-    /// </value>
-    public LocalCertificateSelectionCallback ClientCertificateSelectionCallback
-    {
-      get {
-        return _certSelectionCallback;
-      }
-
-      set {
-        lock (_forConn) {
-          var msg = checkIfAvailable (false, false);
-          if (msg != null) {
-            _logger.Error (msg);
-            error (
-              "An error has occurred in setting the client certificate selection callback.",
-              null);
-
-            return;
-          }
-
-          _certSelectionCallback = value;
-        }
-      }
-    }
-
     /// <summary>
     /// Gets or sets the compression method used to compress the message on the WebSocket
     /// connection.
@@ -1335,7 +1299,8 @@ namespace WebSocketSharp
 
       if (_secure) {
         var conf = SslConfiguration;
-        if (conf.TargetHost != _uri.DnsSafeHost)
+        var host = conf.TargetHost;
+        if (host != _uri.DnsSafeHost)
           throw new WebSocketException (
             CloseStatusCode.TlsHandshakeFailure, "An invalid host name is specified.");
 
@@ -1344,12 +1309,10 @@ namespace WebSocketSharp
             _stream,
             false,
             conf.ServerCertificateValidationCallback,
-            _certSelectionCallback ??
-              ((sender, targetHost, localCertificates, remoteCertificate, acceptableIssuers) =>
-                null));
+            conf.ClientCertificateSelectionCallback);
 
           sslStream.AuthenticateAsClient (
-            conf.TargetHost,
+            host,
             conf.ClientCertificates,
             conf.EnabledSslProtocols,
             conf.CheckCertificateRevocation);