diff --git a/mozilla/widget/src/os2/nsFrameWindow.cpp b/mozilla/widget/src/os2/nsFrameWindow.cpp
index 571a060f091..facce124d4e 100644
--- a/mozilla/widget/src/os2/nsFrameWindow.cpp
+++ b/mozilla/widget/src/os2/nsFrameWindow.cpp
@@ -441,6 +441,12 @@ MRESULT nsFrameWindow::FrameMessage( ULONG msg, MPARAM mp1, MPARAM mp2)
             }
          }
          break;
+      /* To simulate Windows better, we need to send a focus message to the */
+      /* client when the frame is activated */
+      case WM_ACTIVATE:
+         if (SHORT1FROMMP(mp1))
+           WinPostMsg(mWnd, WM_FOCUSCHANGED, 0, MPFROM2SHORT(1,0));
+         break;
    }
 
    if( !bDone)
diff --git a/mozilla/widget/src/os2/nsWindow.cpp b/mozilla/widget/src/os2/nsWindow.cpp
index 68dfb0204ce..24734a03a41 100644
--- a/mozilla/widget/src/os2/nsWindow.cpp
+++ b/mozilla/widget/src/os2/nsWindow.cpp
@@ -2608,7 +2608,9 @@ PRBool nsWindow::ProcessMessage( ULONG msg, MPARAM mp1, MPARAM mp2, MRESULT &rc)
               printf("[%x] NS_GOTFOCUS (%d)\n", this, mWindowIdentifier);
 #endif
               result = DispatchFocus(NS_GOTFOCUS, isMozWindowTakingFocus);
-              if (gJustGotActivate) {
+              /* If mp1 is 0, this is the special WM_FOCUSCHANGED we got */
+              /* from the frame activate, so act like we just got activated */
+              if (gJustGotActivate || mp1 == 0) {
                 gJustGotActivate = PR_FALSE;
                 gJustGotDeactivate = PR_FALSE;
 #ifdef DEBUG_FOCUS