diff --git a/configure.in b/configure.in
index 94ecbed9f..35ba657f9 100644
--- a/configure.in
+++ b/configure.in
@@ -285,12 +285,12 @@ AC_ARG_WITH(lua-include,
 if test "$with_lua" != no; then
   aegisub_save_LDFLAGS="$LDFLAGS"
   
-  LDFLAGS="$LDFLAGS -L$lua_lib_dir"
+  LDFLAGS="$LDFLAGS $lua_lib_dir"
   AC_CHECK_LIB([lua], [lua_call], LUA_LDFLAGS="$lua_lib_dir -llua", with_lua_lib="no")
   LDFLAGS="$aegisub_save_LDFLAGS"
 
   aegisub_save_CPPFLAGS="$CPPFLAGS"
-  CPPFLAGS="$CPPFLAGS -I$lua_include_dir"
+  CPPFLAGS="$CPPFLAGS $lua_include_dir"
   AC_CHECK_HEADER([lua.h],[LUA_CPPFLAGS="$lua_include_dir"], with_lua_include="no")
   CPPFLAGS="$aegisub_save_CPPFLAGS"