session variable appears to lose value in web.py application over Apache

I'm creating an application on web.py. I use session variables to store some values. All of these worked perfec开发者_运维问答tly fine in web.py's integrated server. I've now installed flups and configured the app to run on my apache server. The session file gets created. However on every submit (GET and POST), the session variables are initialized to their default values. Any reasons why this could happen??

Adding code:

Initialization

session = web.session.Session(app, web.session.DiskStore('sessions'), initializer={'valid': 'false')

Setting the value

session._initializer['valid']='true'

The code works for the web.py integrated server.