Help with accessing finance services

[Timbo]

I have some .Net code which allows me to authenticate a user once i
pass in a name and password i.e.

i.e. a request to https://www.google.com/accounts/ClientLogin
PostData =
accountType=hosted_OR_google&email=someon...@gmail.com&Passwd=someonespassword&service=finance&source=MyComp-
MyApp-.01

This returns an SID, LSID and Auth. I keep a copy of the auth code
returned.

I then make a second request (Get) to

http://finance.google.com/finance/feeds/default/portfolios
1st Header = GData-Version: {value}2
2nd Header = Authorization: GoogleLogin auth={value}AuthTokenFromAbove

This produces a 403 (unauthorised) although i am passing in the Auth
code (ONLY) in the second header as the documentation states (So i am
using an authenticated user)

Could anyone explain how to overcome this problem as i am running as a
authorised user but something doesnt seem to add up, therefore not
allowing me to access the portfolios under this account?

Thanks