diff --git a/stepmania/Themes/default/Scripts/Debug.lua b/stepmania/Themes/default/Scripts/Debug.lua
new file mode 100644
index 0000000000..1cf247a375
--- /dev/null
+++ b/stepmania/Themes/default/Scripts/Debug.lua
@@ -0,0 +1,88 @@
+if not debug then
+	-- stubs
+	debug = {}
+	debug.traceback = function() return "" end
+	return
+end
+
+-- Override debug.traceback.
+function debug.traceback(...)
+	local thread = coroutine.running()
+	local msg = ""
+	local level = 1
+	local args = {...};
+	
+	if type(args[1]) == "thread" then thread = args[1]; table.remove(args) end
+	if type(args[1]) == "string" then msg = args[1]; table.remove(args) end
+	if type(args[1]) == "number" then level = args[1]; table.remove(args) end
+
+	if thread == coroutine.running() then
+		level = level + 1 -- skip this function
+	end
+
+	local stack = {}
+	repeat
+		local info = debug.getinfo(level, "Sln");
+		table.insert( stack, info );
+		level = level + 1
+	until not info
+
+	if #stack == 0 then
+		return "";
+	end
+
+	-- The original caller is usually C; remove it.
+	if( stack[#stack].what == "C" ) then
+		table.remove( stack );
+	end
+	local function FormatFrame(level, frame)
+		local sFrameInfo = ""
+		sFrameInfo = sFrameInfo .. "#" .. level .. "  ";
+		if( frame.what == "tail" ) then
+		--      sFrameInfo = sFrameInfo .. "(tail call)"
+		--      return sFrameInfo
+		elseif( frame.what == "main" ) then
+			sFrameInfo = sFrameInfo .. "main in "
+		elseif frame.name then
+			sFrameInfo = sFrameInfo .. frame.name .. "() in "
+		else
+			sFrameInfo = sFrameInfo .. "... in ";
+		end
+			sFrameInfo = sFrameInfo .. frame.short_src
+
+		if frame.currentline ~= -1 then
+			sFrameInfo = sFrameInfo .. ":" .. frame.currentline
+		end
+
+		return sFrameInfo
+	end
+
+	local FrameInfo = {}
+	for level, frame in ipairs(stack) do
+		FrameInfo[level] = FormatFrame(level, frame)
+	end
+	return table.concat( FrameInfo, "\n" );
+end
+
+-- (c) 2006 Glenn Maynard
+-- All rights reserved.
+--
+-- Permission is hereby granted, free of charge, to any person obtaining a
+-- copy of this software and associated documentation files (the
+-- "Software"), to deal in the Software without restriction, including
+-- without limitation the rights to use, copy, modify, merge, publish,
+-- distribute, and/or sell copies of the Software, and to permit persons to
+-- whom the Software is furnished to do so, provided that the above
+-- copyright notice(s) and this permission notice appear in all copies of
+-- the Software and that both the above copyright notice(s) and this
+-- permission notice appear in supporting documentation.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+-- OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+-- MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
+-- THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
+-- INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
+-- OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+-- OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+-- OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+-- PERFORMANCE OF THIS SOFTWARE.