diff --git a/src/msw/notebook.cpp b/src/msw/notebook.cpp
index ff7022558c..a231fe161b 100644
--- a/src/msw/notebook.cpp
+++ b/src/msw/notebook.cpp
@@ -421,12 +421,11 @@ WXDWORD wxNotebook::MSWGetStyle(long style, WXDWORD *exstyle) const
     else if ( style & wxBK_RIGHT )
         tabStyle |= TCS_VERTICAL | TCS_RIGHT;
 
-    // ex style
     if ( exstyle )
     {
         // note that we never want to have the default WS_EX_CLIENTEDGE style
         // as it looks too ugly for the notebooks
-        *exstyle = 0;
+        *exstyle &= ~WS_EX_CLIENTEDGE;
     }
 
     return tabStyle;