Lighttpd

hi i'm using 1.4.28 in the linux board, works fine.

Now we want to add login window when access the webpage.
I added auth part in the conf file.

server.modules += ("mod_auth")
auth.debug=2
auth.backend = "plain"
auth.backend.plain.userfile = "/opt/ultra/config/web_password"

auth.require = ("/" =>
(
"method" => "basic",
"realm" => "Password protected",
"require" => "user=admin"
)

When login, if i type "admin", and my password, it works fine.

Now the request is to prefill "admin" in the webpage to save typing.
And this is a MUST requirement.

Anyone can help ?
I tried to setup cookies from perl CGI script, but what's the cookie name for this login windows ?

Many thanks !