[TYPO3] Login box with Typo3

[Fred]

Hello,
I still have a problem with my TS Login box. I inserted this TS :
#disclaimer
[loginUser = *]
tt_content.text{
    5 = TEXT
    5.value = coucou
}
[else]
temp.loginbox = COA
temp.loginbox{
    10 = TEXT
    10.value = You must be a member to access this part.
    10.wrap = <b>|</b><br /><br />
    20 = FORM
    20.data = Username:|*username=input || Password:|*userident=password 
|| Login|submit|Login
    20.layout = <div class="my_label">###LABEL###</div></div 
class="my_field">###FIELD###</div>
    20.wrap = <div id="my_loginbox">|</div>
    }

page.10.subparts.zone_normal>
page.10.subparts.zone_normal < temp.loginbox

[end]

But I can't find out where or how to set this form as a loginbox. The 
conditions works but not the form.
I checked on some forums but everytime I found the answer "use an 
extension", which is right, but not showing me my mistake.

If anybody have a clue, thanks a lot.