cache_page(per-page-cache) is not working correctly.

I've integrated django-mobile into my website along with Django Cache enabled but I noticed that the per-page-cache were not read and the framework sends database queries even though the pages exist in cache.

After some investigation, I found out that the issue was caused by cache_page and CacheFlavourMiddleware not taking into account the sequence of the cache process.

Expected Sequence: 
Set "HTTP_X_FLAVOUR" header -> FetchFromCacheMiddleware -> Set "Vary: X-Flavour" header -> UpdateCacheMiddleware

Current Sequence:
FetchFromCacheMiddleware -> Set "HTTP_X_FLAVOUR" header -> Set "Vary: X-Flavour" header -> UpdateCacheMiddleware

So FetchFromCacheMiddleware always looks for invalid cache.