diff --git a/mingw-w64-crt/revstamp.h b/mingw-w64-crt/revstamp.h
index dcf316a..b071ee8 100644
--- a/mingw-w64-crt/revstamp.h
+++ b/mingw-w64-crt/revstamp.h
@@ -1,4 +1,4 @@
 /* Do not edit. Autogenerated.  */
-#define __MINGW_W64_REV	"4976"
-#define __MINGW_W64_REV_STAMP "2012-05-03"
+#define __MINGW_W64_REV	"4981"
+#define __MINGW_W64_REV_STAMP "2012-05-07"
 
diff --git a/mingw-w64-headers/include/ChangeLog b/mingw-w64-headers/include/ChangeLog
index e468c8e..7808c25 100644
--- a/mingw-w64-headers/include/ChangeLog
+++ b/mingw-w64-headers/include/ChangeLog
@@ -1,3 +1,7 @@
+2012-05-07  Ozkan Sezer  <sezeroz@gmail.com>
+
+	* dwmapi.h: Fixed all function prototypes to be WINAPI.
+
 2012-04-28  Jonathan Liu  <net147@users.sourceforge.net>
 
 	* wlanapi.h: Fixed incorrectly nested if blocks.
diff --git a/mingw-w64-headers/include/dwmapi.h b/mingw-w64-headers/include/dwmapi.h
index d7ded47..809d589 100644
--- a/mingw-w64-headers/include/dwmapi.h
+++ b/mingw-w64-headers/include/dwmapi.h
@@ -162,7 +162,7 @@
 /* FIXME: use WINVER instead? */
 #if _WIN32_WINNT >= 0x0600
 
-BOOL DwmDefWindowProc(
+BOOL WINAPI DwmDefWindowProc(
     HWND hwnd,
     UINT msg,
     WPARAM wParam,
@@ -170,84 +170,84 @@
     LRESULT *plResult
 );
 
-HRESULT DwmEnableBlurBehindWindow(
+HRESULT WINAPI DwmEnableBlurBehindWindow(
     HWND hWnd,
     const DWM_BLURBEHIND *pBlurBehind
 );
 
-HRESULT DwmEnableComposition(
+HRESULT WINAPI DwmEnableComposition(
     UINT uCompositionAction
 );
 
-HRESULT DwmEnableMMCSS(
+HRESULT WINAPI DwmEnableMMCSS(
     BOOL fEnableMMCSS
 );
 
-HRESULT DwmExtendFrameIntoClientArea(
+HRESULT WINAPI DwmExtendFrameIntoClientArea(
     HWND hWnd,
     const MARGINS *pMarInset
 );
 
-HRESULT DwmGetColorizationColor(
+HRESULT WINAPI DwmGetColorizationColor(
     DWORD *pcrColorization,
     BOOL *pfOpaqueBlend
 );
 
-HRESULT DwmGetCompositionTimingInfo(
+HRESULT WINAPI DwmGetCompositionTimingInfo(
     HWND hwnd,
     DWM_TIMING_INFO *pTimingInfo
 );
 
-HRESULT DwmGetWindowAttribute(
+HRESULT WINAPI DwmGetWindowAttribute(
     HWND hwnd,
     DWORD dwAttribute,
     PVOID pvAttribute,
     DWORD cbAttribute
 );
 
-HRESULT DwmIsCompositionEnabled(
+HRESULT WINAPI DwmIsCompositionEnabled(
     BOOL *pfEnabled
 );
 
-HRESULT DwmModifyPreviousDxFrameDuration(
+HRESULT WINAPI DwmModifyPreviousDxFrameDuration(
     HWND hwnd,
     INT cRefreshes,
     BOOL fRelative
 );
 
-HRESULT DwmQueryThumbnailSourceSize(
+HRESULT WINAPI DwmQueryThumbnailSourceSize(
     HTHUMBNAIL hThumbnail,
     PSIZE pSize
 );
 
-HRESULT DwmRegisterThumbnail(
+HRESULT WINAPI DwmRegisterThumbnail(
     HWND hwndDestination,
     HWND *hwndSource,
     PHTHUMBNAIL phThumbnailId
 );
 
-HRESULT DwmSetDxFrameDuration(
+HRESULT WINAPI DwmSetDxFrameDuration(
     HWND hwnd,
     INT cRefreshes
 );
 
-HRESULT DwmSetPresentParameters(
+HRESULT WINAPI DwmSetPresentParameters(
     HWND hwnd,
     DWM_PRESENT_PARAMETERS *pPresentParams
 );
 
-HRESULT DwmSetWindowAttribute(
+HRESULT WINAPI DwmSetWindowAttribute(
     HWND hwnd,
     DWORD dwAttribute,
     LPCVOID pvAttribute,
     DWORD cbAttribute
 );
 
-HRESULT DwmUnregisterThumbnail(
+HRESULT WINAPI DwmUnregisterThumbnail(
     HTHUMBNAIL hThumbnailId
 );
 
-HRESULT DwmUpdateThumbnailProperties(
+HRESULT WINAPI DwmUpdateThumbnailProperties(
     HTHUMBNAIL hThumbnailId,
     const DWM_THUMBNAIL_PROPERTIES *ptnProperties
 );