Strange text in login panel

[ITwiz]

Hi, i just discovered strange error :/
When i go to my page /admin/index.php i get strange text, like this:

{CONTROL_PANEL}
{USERNAME}:
{PASSWORD}:
{LOGIN}

and etc... What's wrong ? I think, there are some problems with language file ? :/

i added screenshot.


Just noticed that, after login and loguot this problem disappears, but after cookies cleanup it shows strange text again.