Login module/form doesnt work in frameset.

hi to all,

please help me solve this problem, my site is using index.htm as startup page. the startup page has divided into two frameset. one frameset is blank, the main frameset is linked to index.php which failed to login. you can test this setup on your local webserver. by typing:

http://localhost/index.htm

the content of index.htm is:
-------------------------------------------
<html>
<head>
<title>NMCIREMP Home Page</title>
<meta name="keywords" content="nmciremp">
<meta name="description" content="nmciremp">
</head>
<frameset border="0" rows="100%,*">
<frame name="mainFrame" src="http://127.0.0.1/index.php">
</frameset>
<noframes>
<body>
</body>
</noframes>
</html>
--------------------------------------------

thanks in advance.