diff --git a/tests/test.cpp b/tests/test.cpp
index 5e2f6c5c7d..ba853d53ea 100644
--- a/tests/test.cpp
+++ b/tests/test.cpp
@@ -360,6 +360,37 @@ extern bool IsAutomaticTest()
 
 #if wxUSE_GUI
 
+bool EnableUITests()
+{
+    static int s_enabled = -1;
+    if ( s_enabled == -1 )
+    {
+        // Allow explicitly configuring this via an environment variable under
+        // all platforms.
+        wxString enabled;
+        if ( wxGetEnv("WX_UI_TESTS", &enabled) )
+        {
+            if ( enabled == "1" )
+                s_enabled = 1;
+            else if ( enabled == "0" )
+                s_enabled = 0;
+            else
+                wxFprintf(stderr, "Unknown \"WX_UI_TESTS\" value \"%s\" ignored.\n", enabled);
+        }
+
+        if ( s_enabled == -1 )
+        {
+#ifdef __WXMSW__
+            s_enabled = 1;
+#else // !__WXMSW__
+            s_enabled = 0;
+#endif // __WXMSW__/!__WXMSW__
+        }
+    }
+
+    return s_enabled == 1;
+}
+
 void DeleteTestWindow(wxWindow* win)
 {
     if ( !win )
diff --git a/tests/testprec.h b/tests/testprec.h
index 8bbaf4be70..f5661446ed 100644
--- a/tests/testprec.h
+++ b/tests/testprec.h
@@ -10,13 +10,14 @@
 // this allows the tests that do not rely on it to run on platforms that don't
 // support it.
 //
-// FIXME: And while OS X does support it, more or less, too many tests
-//        currently fail under it so disable all interactive tests there. They
-//        should, of course, be reenabled a.s.a.p.
-#if wxUSE_UIACTIONSIMULATOR && !defined(__WXOSX__)
-    #define WXUISIM_TEST(test) CPPUNIT_TEST(test)
+// Unfortunately, currently too many of the UI tests fail on non-MSW platforms,
+// so they're disabled there by default. This really, really needs to be fixed,
+// but for now having the UI tests always failing is not helpful as it prevents
+// other test failures from being noticed, so disable them there.
+#if wxUSE_UIACTIONSIMULATOR
+    #define WXUISIM_TEST(test) if ( EnableUITests() ) { CPPUNIT_TEST(test) }
 #else
-    #define WXUISIM_TEST(test) (void)0
+    #define WXUISIM_TEST(test)
 #endif
 
 // define wxHAVE_U_ESCAPE if the compiler supports \uxxxx character constants
@@ -169,6 +170,9 @@ private:
 
 #if wxUSE_GUI
 
+// Return true if the UI tests are enabled, used by WXUISIM_TEST().
+extern bool EnableUITests();
+
 // Helper function deleting the window without asserts (and hence exceptions
 // thrown from its dtor!) even if it has mouse capture.
 void DeleteTestWindow(wxWindow* win);