WordPress MU

the problem am facing is if some new member register on my site after pressing the sign-up button the next pages shows like "You've got a new blog" there the adress shows like http://www.mydomain.com/username
but still i can acess http://www.username.mydomain.com
but i want to show the after sign-up page like

http://www.username.mydomain.com
http://www.username.mydomain.com/wp-login.php

plzz help me... where should i make the changes

did you select vHost?

this is include ServerAlias and DNS catch-all. If you don't have cPanel, ask to webhost admin for ServerAlias and DNS catch-all

thanks 4 ur advice federico
where do i select vHost?
i have cpanel...my site uploaded at hostgator...after my instalation only the hostgator team enabled mod_rewrite and also setup wildcard DNS for my domain...sometime am getting this fatal error...plzz help

At start page for install clik on vHost Support enable.

Did you enable ServerAlias for your domain?

I think you install again, before you clean your database.

thanks fed..thanks a lot...................i re-installed it...now everthing cool...

thanks again