Hello sidhu688,
Is that your entire code? Whenever IE renders things differently from a good browser, like FF, I always suspect a missing DocType.
See the link about DocTypes in my signature line.
See if this helps -
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<body>
<input type="button" id="btn1" value="test test test" />
<input type="button" id="btn1" value="test" />
</body>
</html>