diff --git a/win32/wconfig.cpp b/win32/wconfig.cpp
index b2feb48e..2a817bcb 100644
--- a/win32/wconfig.cpp
+++ b/win32/wconfig.cpp
@@ -221,6 +221,9 @@ void WinDeleteRecentGamesList ();
 
 HANDLE configMutex = NULL;
 
+extern TCHAR multiRomA[MAX_PATH]; // lazy, should put in sGUI and add init to {0} somewhere
+extern TCHAR multiRomB[MAX_PATH];
+
 void S9xParseArg (char **argv, int &i, int argc)
 {
 	if (strcasecmp (argv [i], "-restore") == 0)
@@ -236,11 +239,16 @@ void S9xParseArg (char **argv, int &i, int argc)
 	{
 		GUI.FullScreen = true;
 	}
+	else if (!strcasecmp(argv[i], "-cartb"))
+	{
+		Settings.Multi = TRUE; // only used to signal winmain
+		if (i + 1 < argc)
+		{
+			lstrcpyn(multiRomB, _tFromChar(argv[++i]), MAX_PATH);
+		}
+	}
 }
 
-extern TCHAR multiRomA [MAX_PATH]; // lazy, should put in sGUI and add init to {0} somewhere
-extern TCHAR multiRomB [MAX_PATH];
-
 void WinSetDefaultValues ()
 {
 	// TODO: delete the parts that are already covered by the default values in WinRegisterConfigItems
diff --git a/win32/wsnes9x.cpp b/win32/wsnes9x.cpp
index c16d3b3a..e5209524 100644
--- a/win32/wsnes9x.cpp
+++ b/win32/wsnes9x.cpp
@@ -327,6 +327,9 @@ extern FILE *trace_fs;
 extern SCheatData Cheat;
 extern bool8 do_frame_adjust;
 
+TCHAR multiRomA[MAX_PATH] = { 0 }; // lazy, should put in sGUI and add init to {0} somewhere
+TCHAR multiRomB[MAX_PATH] = { 0 };
+
 HINSTANCE g_hInst;
 
 #ifdef DEBUGGER
@@ -1551,10 +1554,6 @@ bool WinMoviePlay(LPCTSTR filename)
 	return true;
 }
 
-TCHAR multiRomA [MAX_PATH] = {0}; // lazy, should put in sGUI and add init to {0} somewhere
-TCHAR multiRomB [MAX_PATH] = {0};
-
-
 static bool startingMovie = false;
 
 HWND cheatSearchHWND = NULL;
@@ -3447,8 +3446,18 @@ int WINAPI WinMain(
         MessageBox( GUI.hWnd, Languages[ GUI.Language].errFrameTimer, TEXT("Snes9X - Frame Timer"), MB_OK | MB_ICONINFORMATION);
     }
 
-	if(rom_filename)
-		LoadROM(rom_filename);
+	if (rom_filename)
+	{
+		if (Settings.Multi) // we found -cartB parameter
+		{
+			lstrcpy(multiRomA, rom_filename); // for the mutli cart dialog
+			LoadROM(rom_filename, multiRomB);
+		}
+		else
+		{
+			LoadROM(rom_filename);
+		}
+	}
 
 	S9xUnmapAllControls();
 	S9xSetupDefaultKeymap();