Backend Link Redirects To Login Page

Hello
i have installed wordpress 3.0.1 on https://blogtest.lawcrossing.com domain
and i have created the site like https://hound.blogtest.lawcrossing.com, and i can
access its admin from backend link in site listing, automatically logged in.

But when i edit the new site like https://blogtest.hound.com , i can’t access
the admin from backend link instead its shows me login page. I cant understand this
behaviour. Can any one help why this is happening?