diff --git a/dlls/comctl32/commctrl.c b/dlls/comctl32/commctrl.c
index c21cae31306..7e44e0304d5 100644
--- a/dlls/comctl32/commctrl.c
+++ b/dlls/comctl32/commctrl.c
@@ -693,12 +693,13 @@ CreateToolbarEx (HWND hwnd, DWORD style, UINT wID, INT nBitmaps,
        SendMessageW (hwndTB, TB_SETBITMAPSIZE, 0,
                      MAKELPARAM((WORD)dxBitmap, (WORD)dyBitmap));
 
-       if (dxButton <= 0)
-           dxButton = 24;
-       if (dyButton <= 0)
-           dyButton = 22;
-       SendMessageW (hwndTB, TB_SETBUTTONSIZE, 0,
-                     MAKELPARAM((WORD)dxButton, (WORD)dyButton));
+       if (dxButton < 0)
+           dxButton = dxBitmap;
+       if (dyButton < 0)
+           dyButton = dyBitmap;
+       /* TB_SETBUTTONSIZE -> TB_SETBITMAPSIZE bug introduced for Windows compatibility */
+       if (dxButton != 0 && dyButton != 0)
+            SendMessageW(hwndTB, TB_SETBITMAPSIZE, 0, MAKELPARAM(dxButton, dyButton));
 
 
 	/* add bitmaps */
diff --git a/dlls/comctl32/tests/toolbar.c b/dlls/comctl32/tests/toolbar.c
index 164644e029f..b58329541d6 100644
--- a/dlls/comctl32/tests/toolbar.c
+++ b/dlls/comctl32/tests/toolbar.c
@@ -869,6 +869,45 @@ static void test_sizes(void)
     DestroyWindow(hToolbar);
 }
 
+
+static void test_createtoolbarex()
+{
+    HWND hToolbar;
+    TBBUTTON btns[3];
+    ZeroMemory(&btns, sizeof(btns));
+
+    hToolbar = CreateToolbarEx(hMainWnd, WS_VISIBLE, 1, 16, GetModuleHandle(NULL), IDB_BITMAP_128x15, btns,
+        3, 20, 20, 16, 16, sizeof(TBBUTTON));
+    CHECK_IMAGELIST(16, 20, 20);
+    compare((int)SendMessage(hToolbar, TB_GETBUTTONSIZE, 0, 0), 0x1a001b, "%x");
+    DestroyWindow(hToolbar);
+
+    hToolbar = CreateToolbarEx(hMainWnd, WS_VISIBLE, 1, 16, GetModuleHandle(NULL), IDB_BITMAP_128x15, btns,
+        3, 4, 4, 16, 16, sizeof(TBBUTTON));
+    CHECK_IMAGELIST(32, 4, 4);
+    compare((int)SendMessage(hToolbar, TB_GETBUTTONSIZE, 0, 0), 0xa000b, "%x");
+    DestroyWindow(hToolbar);
+
+    hToolbar = CreateToolbarEx(hMainWnd, WS_VISIBLE, 1, 16, GetModuleHandle(NULL), IDB_BITMAP_128x15, btns,
+        3, 0, 8, 12, 12, sizeof(TBBUTTON));
+    CHECK_IMAGELIST(16, 12, 12);
+    compare((int)SendMessage(hToolbar, TB_GETBUTTONSIZE, 0, 0), 0x120013, "%x");
+    DestroyWindow(hToolbar);
+
+    hToolbar = CreateToolbarEx(hMainWnd, WS_VISIBLE, 1, 16, GetModuleHandle(NULL), IDB_BITMAP_128x15, btns,
+        3, -1, 8, 12, 12, sizeof(TBBUTTON));
+    CHECK_IMAGELIST(16, 12, 8);
+    compare((int)SendMessage(hToolbar, TB_GETBUTTONSIZE, 0, 0), 0xe0013, "%x");
+    DestroyWindow(hToolbar);
+
+    hToolbar = CreateToolbarEx(hMainWnd, WS_VISIBLE, 1, 16, GetModuleHandle(NULL), IDB_BITMAP_128x15, btns,
+        3, -1, 8, -1, 12, sizeof(TBBUTTON));
+    CHECK_IMAGELIST(16, 16, 8);
+    compare((int)SendMessage(hToolbar, TB_GETBUTTONSIZE, 0, 0), 0xe0017, "%x");
+    DestroyWindow(hToolbar);
+}
+
+
 START_TEST(toolbar)
 {
     WNDCLASSA wc;
@@ -899,6 +938,7 @@ START_TEST(toolbar)
     test_add_string();
     test_hotitem();
     test_sizes();
+    test_createtoolbarex();
 
     PostQuitMessage(0);
     while(GetMessageA(&msg,0,0,0)) {