Session info is getting erased


i finally got web services to work between two apps that i am currently
working on. the application that serves the API stores the user id in a
session when the user logs in. but when i use the client application and
then go back to the server app, my session is erased and i have a
message something like "Couldn’t find User without an ID "

any ideas why this is happening? both apps are also in development mode
right now. i don’t know if that means anything or not.