dotcloud is always waking up my app

I have a dotcloud app written on top of nodejs Since yesterday when accessing to my app, dot cloud always says to me that is waking up my app.

It take a long time, and then load the page, but there is resources on my pages that are never loaded. Some resources like images receive a 302 response with the page saying that it's waking up the app.

Does any one have an idea on what is happening??