How do i add new button to logon screen [LOGONUI] in win7

i mention to add a new button to logon screen!
their is the ease of access button that i can replace.. but i don't want to replace it
i want to create new button!
hope it was understood
if not contact me in skype : w4rblood

New button for what? I still don't quite understand.

Windows itself will not allow you to place another button next to the "ease of access" button, at least as far as I know. There may be a way to do it via registry editing or third party software. Kind of doubt it though. The existence of the "ease of access" button itself is somewhat of a security issue already.