How to access WordPress from separate sub-directory

i have installed wordpress, and am running it pretty simply with most defaults, etc, and only a small number of users.

on this site, i created a sub-directory and dupliated the ./index.php file so as to recreate the menu bars, etc. the only difference is there is no content in the main div tags.

this sub-section uses different database tables in the same database, but i would like to have the wordpress users to link up the users of this second database.

on the page, i have called “$user = wp_get_current_user();” and then:
echo $user->ID;”
but it doesnt return anything.

i have already logged in to the site, then typed in the full URL to the subsection so i think it carries the session id’s and stuff… then i would like to return the current user.

any help with this issue would be appreciated.

regards,

jingo_man