Member-Login not working on IIS6, when in Virtual Directory

[Uwe]

Hi,
I'm currently developing an ASP.NET application with my own
MembershipProvider. Login works fine on my local machine (IIS7) in a virtual
directory of IIS. I just deployed the application to a Win2k3 webserver and
put it into a virtual directory. Unfortunately, login doesn't work there.
When I change the root path of the website to the solution's directory, so
that it is directly accessible without a virtual directory, login works
fine.

Both use the same application pool and the same settings. What can be the
reason for this problem?

Thanks!