calling a web service protected by RSA SecurID

Hi,

my client has an extranet IIS web server protected by RSA SecurID.
it's running my asp.net 1.1 application. when they use the web app
from a browser they have to log in to RSA, then they see the login
screen for our application (forms authentication) and everything is
fine.

however, when they use our winforms client application to access a web
service (which is part of the same web app), it doesn't work. we are
handling HTTP 401 responses correctly in the windows client but I
guess SecurID is not using this mechanism.

anyone know how I can get a .Net 1.1 winforms application to connect
to a web service that is proected by SecurID

TIA for any thoughts.

Andy