diff --git a/CHANGES.md b/CHANGES.md
index fae7c2d78b..9357f529da 100755
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -40,6 +40,7 @@ Bug Fixes
 * [#382](https://github.com/twall/jna/pull/382): Fixed memory allocation in `com.sun.jna.platform.win32.WTypes.LPWSTR` and `LPSTR` constructors - [@junak-michal](https://github.com/junak-michal).
 * Fix publish doc links - [@bhamail](https://github.com/bhamail).
 * [#388](https://github.com/twall/jna/issues/388): Ensure native library always opened with provided flags - [@zolyfarkas](https://github.com/zolyfarkas).  
+* [#403](https://github.com/twall/jna/pull/403): Make com.sun.jna.platform.win32.COM.COMUtils.SUCCEEDED and FAILED conform to MSDN specification for said macros - [@lwahonen](https://github.com/lwahonen).
 
 Release 4.1
 ===========
diff --git a/contrib/platform/src/com/sun/jna/platform/win32/COM/COMBindingBaseObject.java b/contrib/platform/src/com/sun/jna/platform/win32/COM/COMBindingBaseObject.java
index eddbbd48f8..9bdfcace8d 100644
--- a/contrib/platform/src/com/sun/jna/platform/win32/COM/COMBindingBaseObject.java
+++ b/contrib/platform/src/com/sun/jna/platform/win32/COM/COMBindingBaseObject.java
@@ -73,8 +73,7 @@ public COMBindingBaseObject(CLSID clsid, boolean useActiveInstance,
             int dwClsContext) {
         // Initialize COM for this thread...
         HRESULT hr = Ole32.INSTANCE.CoInitializeEx(null, Ole32.COINIT_APARTMENTTHREADED);
-        if (hr.intValue() == 1) // Already initialized, no problem
-            hr = new HRESULT(0);
+
         if (COMUtils.FAILED(hr)) {
             Ole32.INSTANCE.CoUninitialize();
             throw new COMException("CoInitialize() failed!");
@@ -108,8 +107,6 @@ public COMBindingBaseObject(String progId, boolean useActiveInstance,
             int dwClsContext) throws COMException {
         // Initialize COM for this thread...
         HRESULT hr = Ole32.INSTANCE.CoInitializeEx(null, Ole32.COINIT_APARTMENTTHREADED);
-        if (hr.intValue() == 1) // Already initialized, no problem
-            hr = new HRESULT(0);
 
         if (COMUtils.FAILED(hr)) {
             this.release();
diff --git a/contrib/platform/src/com/sun/jna/platform/win32/COM/COMUtils.java b/contrib/platform/src/com/sun/jna/platform/win32/COM/COMUtils.java
index b362d0c9a8..d2e15e44a0 100644
--- a/contrib/platform/src/com/sun/jna/platform/win32/COM/COMUtils.java
+++ b/contrib/platform/src/com/sun/jna/platform/win32/COM/COMUtils.java
@@ -38,6 +38,8 @@ public abstract class COMUtils {
 
     /** The Constant CO_E_NOTINITIALIZED. */
     public static final int S_OK = 0;
+    public static final int S_FALSE = 1;
+    public static final int E_UNEXPECTED=0x8000FFFF;
 
     /**
      * Succeeded.
@@ -58,10 +60,7 @@ public static boolean SUCCEEDED(HRESULT hr) {
      * @return true, if successful
      */
     public static boolean SUCCEEDED(int hr) {
-        if (hr == S_OK)
-            return true;
-        else
-            return false;
+        return hr >= 0;
     }
 
     /**
@@ -83,7 +82,7 @@ public static boolean FAILED(HRESULT hr) {
      * @return true, if successful
      */
     public static boolean FAILED(int hr) {
-        return (hr != S_OK);
+        return hr < 0;
     }
 
     /**
diff --git a/contrib/platform/test/com/sun/jna/platform/win32/COM/COMUtilsTest.java b/contrib/platform/test/com/sun/jna/platform/win32/COM/COMUtilsTest.java
new file mode 100644
index 0000000000..56aac85142
--- /dev/null
+++ b/contrib/platform/test/com/sun/jna/platform/win32/COM/COMUtilsTest.java
@@ -0,0 +1,18 @@
+package com.sun.jna.platform.win32.COM;
+
+import junit.framework.TestCase;
+
+public class COMUtilsTest extends TestCase {
+
+    public void testSUCCEEDED() throws Exception {
+        assertTrue(COMUtils.SUCCEEDED(COMUtils.S_OK));
+        assertTrue(COMUtils.SUCCEEDED(COMUtils.S_FALSE));
+        assertFalse(COMUtils.SUCCEEDED(COMUtils.E_UNEXPECTED));
+    }
+
+    public void testFAILED() throws Exception {
+        assertFalse(COMUtils.FAILED(COMUtils.S_OK));
+        assertFalse(COMUtils.FAILED(COMUtils.S_FALSE));
+        assertTrue(COMUtils.FAILED(COMUtils.E_UNEXPECTED));
+    }
+}
\ No newline at end of file