Basic Authentication across multiple sites

Hello,

I have 2 websites running on the same IIS7. Both have a separate Application Pools and have Basic Authentication set up on certain subfolders.

If I authenticate against Site1 and then access Site2 in the same session I am again prompted with an authentication box. 

Is it possible to configure IIS such that if I authenticate in Site 1 that it will automatically be picked up in Site2?? The sites are classic asp and use variables like  request.servervariables( auth_user ) etc.

Can I share the application pool or link the sites in some way to achieve this??

Thanks