Multi Site and symlinks

I am new bee to drupal. I want to setup the multi-site environment.

i have following setup structure,

Root Site - www/drupal-6.14
Site1 - www/drupal-6.14/site1
Site2 - www/drupal-6.14/site2
symlinks created for both site1 and site2.

i have separate database for site1 and site2 and root setup also.

Options +FollowSymLinks - is enabled in my .htaccess file.

I am able to navigate all the sites,

http://localhost/drupal-6.14
http://localhost/drupal-6.14/site1
http://localhost/drupal-6.14/site2

ISSUE:
while i am navigating the site as,
http://localhost/drupal-6.14/site1/user - working great, showing me user-login page.
http://localhost/drupal-6.14/site1/site1/user -it is also working, which is wrong. Actually it should show me page not found page rather than user-login page.

Help would be appreciated.