<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" ></meta>
<META HTTP-EQUIV="Cache-Control" CONTENT="no-cache" ></META>
<META HTTP-EQUIV="Pragma" CONTENT="no-cache" ></META>
<title>SEAL UI Test Page</title>
<link rel="stylesheet" href="css/default.css"></title>
<script type="text/javascript" src="js/jquery-1.5.min.js"></script>
<script type="text/javascript" src="js/jquery.mobile-1.0a3.min.js"></script>
<script type="text/javascript">
function validate(){
$.mobile.changePage("main.htm", "slide");
}
</script>
</head>
<body>
<div data-role="page" id="page-content" name="page-content">
<div data-role="header">
<h1>Page Title</h1>
</div>
<div data-role="content">
<p align="center"><img border="0" src="images/seallogolg.png" width="100" height="100" ></img></p>
<table width="90%">
<tr>
<td>
<label for="name">Username:</label>
</td>
<td>
<input type="email" name="username" id="username" value="" placeholder="Username" title="Your name is required." required ></input>
</td>
</tr>
<tr>
<td>
<label for="name">Password:</label>
</td>
<td>
<input type="password" name="password" placeholder="Password" id="password" value="" ></input>
</td>
</tr>
<tr>
<td>
<input type="button" name="button" value="Login" class="ui-btn-hidden" onClick="validate();" ></input>
</td>
</tr>
</table>
<table width="99%">
<tr>
<td colspan="2"><label for="slider">Remember Username and Password:</label>
<fieldset data-role="controlgroup" data-type="horizontal" data-role="fieldcontain" align="center" id="remember">
<input type="radio" name=" radio-choice-a" id="radio-choice-a" value="on" checked="checked" ></input>
<label for="radio-choice-a">On</label>
<input type="radio" name=" radio-choice-a" id="radio-choice-b" value="off" ></input>
<label for="radio-choice-b">Off</label>
</fieldset>
</td>
</tr>
<tr>
<td colspan="2" align="right"> </td>
</tr>
</table>
</div>
<div data-role="footer" data-position="fixed" data-id="1">
<div data-role="navbar">
<ul>
<li><a href="about.htm" data-icon="help">About</a></li>
<li><a href="setup.htm" data-icon="gear">Setup</a></li>
</ul>
</div><!-- /navbar -->
</div>
</div>
</body>
</html>
main.htm(without img tag)
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<div data-role="page" id="mainpage">
</div>
</body>
</html>
main.htm(with img tag) works perfectly
<!DOCTYPE html> <html> <head> </head> <body> <div data-role="page" id="mainpage"> <img > </div> </body> </html>