diff --git a/classpath/java-nio.cpp b/classpath/java-nio.cpp
index 6c3fb14ee5..899982a472 100644
--- a/classpath/java-nio.cpp
+++ b/classpath/java-nio.cpp
@@ -154,17 +154,19 @@ eagain()
 }
 
 bool
-makeNonblocking(JNIEnv* e, int d)
+setBlocking(JNIEnv* e, int d, bool blocking)
 {
 #ifdef WIN32
-  u_long a = 1;
+  u_long a = (blocking ? 0 : 1);
   int r = ioctlsocket(d, FIONBIO, &a);
   if (r != 0) {
     throwIOException(e);
     return false;
   }
 #else
-  int r = fcntl(d, F_SETFL, fcntl(d, F_GETFL) | O_NONBLOCK);
+  int r = fcntl(d, F_SETFL, (blocking
+                             ? (fcntl(d, F_GETFL) & (~O_NONBLOCK))
+                             : (fcntl(d, F_GETFL) | O_NONBLOCK)));
   if (r < 0) {
     throwIOException(e);
     return false;
@@ -231,7 +233,6 @@ doAccept(JNIEnv* e, int s)
   socklen_t length = sizeof(address);
   int r = ::accept(s, &address, &length);
   if (r >= 0) {
-    makeNonblocking(e, r);
     return r;
   } else {
     throwIOException(e);
@@ -260,7 +261,7 @@ doWrite(int fd, const void* buffer, size_t count)
 }
 
 int
-makeSocket(JNIEnv* e, bool blocking = false)
+makeSocket(JNIEnv* e)
 {
 #ifdef WIN32
   static bool wsaInitialized = false;
@@ -279,8 +280,6 @@ makeSocket(JNIEnv* e, bool blocking = false)
     return s;
   }
 
-  if (not blocking) makeNonblocking(e, s);
-
   return s;
 }
 
@@ -311,6 +310,15 @@ Java_java_nio_channels_ServerSocketChannel_natDoListen(JNIEnv *e,
   return s;
 }
 
+extern "C" JNIEXPORT void JNICALL
+Java_java_nio_channels_SocketChannel_configureBlocking(JNIEnv *e,
+                                                       jclass,
+                                                       jint socket,
+                                                       jboolean blocking)
+{
+  setBlocking(e, socket, blocking);
+}
+
 extern "C" JNIEXPORT void JNICALL
 Java_java_nio_channels_SocketChannel_natSetTcpNoDelay(JNIEnv *e,
                                                       jclass,
@@ -325,11 +333,14 @@ Java_java_nio_channels_SocketChannel_natDoConnect(JNIEnv *e,
 						  jclass,
 						  jstring host,
 						  jint port,
+                                                  jboolean blocking,
 						  jbooleanArray retVal)
 {
   int s = makeSocket(e);
   if (e->ExceptionOccurred()) return 0;
 
+  setBlocking(e, s, blocking);
+
   sockaddr_in address;
   init(e, &address, host, port);
   if (e->ExceptionOccurred()) return 0;
@@ -425,7 +436,8 @@ class Pipe {
     address.sin_family = AF_INET;
     address.sin_port = 0;
     address.sin_addr.s_addr = inet_addr("127.0.0.1"); //INADDR_LOOPBACK;
-    listener_ = makeSocket(e, false);
+    listener_ = makeSocket(e);
+    setBlocking(e, listener_, false);
     ::doListen(e, listener_, &address);
 
     socklen_t length = sizeof(sockaddr_in);
@@ -435,7 +447,8 @@ class Pipe {
       throwIOException(e);
     }
 
-    writer_ = makeSocket(e, true);
+    writer_ = makeSocket(e);
+    setBlocking(e, writer_, true);
     connected_ = ::doConnect(e, writer_, &address);
   }
 
@@ -485,8 +498,8 @@ class Pipe {
       return;
     }
 
-    if (makeNonblocking(e, pipe[0])) {
-      makeNonblocking(e, pipe[1]);
+    if (setBlocking(e, pipe[0], false)) {
+      setBlocking(e, pipe[1], false);
     }
   }
 
diff --git a/classpath/java/nio/channels/ServerSocketChannel.java b/classpath/java/nio/channels/ServerSocketChannel.java
index f84c9626bc..5ddbdc0f16 100644
--- a/classpath/java/nio/channels/ServerSocketChannel.java
+++ b/classpath/java/nio/channels/ServerSocketChannel.java
@@ -23,7 +23,7 @@ public class ServerSocketChannel extends SelectableChannel {
     return new ServerSocketChannel();
   }
 
-  public SelectableChannel configureBlocking(boolean v) {
+  public SelectableChannel configureBlocking(boolean v) throws IOException {
     return channel.configureBlocking(v);
   }
 
@@ -61,6 +61,7 @@ public class ServerSocketChannel extends SelectableChannel {
         throw new IllegalArgumentException();
       }
       channel.socket = doListen(a.getHostName(), a.getPort());
+      channel.configureBlocking(channel.isBlocking());
     }
   }
 
diff --git a/classpath/java/nio/channels/SocketChannel.java b/classpath/java/nio/channels/SocketChannel.java
index 33ac011005..c6879d3a8a 100644
--- a/classpath/java/nio/channels/SocketChannel.java
+++ b/classpath/java/nio/channels/SocketChannel.java
@@ -24,21 +24,29 @@ public class SocketChannel extends SelectableChannel
 
   int socket = InvalidSocket;
   boolean connected = false;
+  boolean blocking = true;
 
   public static SocketChannel open() {
     return new SocketChannel();
   }
 
-  public SelectableChannel configureBlocking(boolean v) {
-    if (v) throw new IllegalArgumentException();
+  public SelectableChannel configureBlocking(boolean v) throws IOException {
+    blocking = v;
+    if (socket != InvalidSocket) {
+      configureBlocking(socket, v);
+    }
     return this;
   }
 
+  public boolean isBlocking() {
+    return blocking;
+  }
+
   public Socket socket() {
     return new Handle();
   }
 
-  public boolean connect(SocketAddress address) throws Exception {
+  public boolean connect(SocketAddress address) throws IOException {
     InetSocketAddress a;
     try {
       a = (InetSocketAddress) address;
@@ -46,6 +54,7 @@ public class SocketChannel extends SelectableChannel
       throw new UnsupportedAddressTypeException();
     }
     socket = doConnect(a.getHostName(), a.getPort());
+    configureBlocking(blocking);
     return connected;
   }
 
@@ -56,11 +65,11 @@ public class SocketChannel extends SelectableChannel
     }
   }
 
-  private int doConnect(String host, int port) throws Exception {
+  private int doConnect(String host, int port) throws IOException {
     if (host == null) throw new NullPointerException();
 
     boolean b[] = new boolean[1];
-    int s = natDoConnect(host, port, b);
+    int s = natDoConnect(host, port, blocking, b);
     connected = b[0];
     return s;
   }
@@ -109,11 +118,14 @@ public class SocketChannel extends SelectableChannel
     }
   }
 
+  private static native void configureBlocking(int socket, boolean blocking)
+    throws IOException;
+
   private static native void natSetTcpNoDelay(int socket, boolean on)
     throws SocketException;
 
-  private static native int natDoConnect(String host, int port, boolean[] connected)
-    throws Exception;
+  private static native int natDoConnect(String host, int port, boolean blocking, boolean[] connected)
+    throws IOException;
   private static native int natRead(int socket, byte[] buffer, int offset, int length)
     throws IOException;
   private static native int natWrite(int socket, byte[] buffer, int offset, int length)