invalid json response when using devise plugin

Hey all,

I am using devise. While the data successfully updates to database, it still reports back as an error, and the below error function is executed:

          var options = {             type: 'POST',             url: "/user",             dataType: 'json',             data: $('#dialog-form form:first').serialize(),             error: function(xhr, textStatus, errorThrown) {               alert('An error occurred! ' + errorThrown);             },             success: function(data, textStatus) {               $('body').append( data );             }           };           $.ajax( options );

I get a popup that says:

The page at http://localhost:3000 says:An error occurred! Invalid JSON: <!-- /application.html --> <!DOCTYPE html> <html>   <head>     <meta content='text/html; charset=utf-8' http-equiv='Content-Type'>     <meta content='Lose weight and diet' name='description'>     <meta content='Diet, Lose Weight, name='keywords'>     <title>Diet | IMRS</title>     <link href='/images/favicon.png' rel='shortcut icon' type='image/x-icon'>     <link href='/lab/rss_2.0' rel='alternate' title='Diet RSS Feed' type='application/rss+xml'>     <link href='/lab/atom' rel='alternate' title='Diet Atom Feed' type='application/atom+xml'>     <!-- <link rel="stylesheet" type="text/css" href="/css/basic.css" /> -->     <link href="/stylesheets/basic.css?1299515867" media="screen" rel="stylesheet" type="text/css" />     <link href="/stylesheets/blog_kit.css?1299515867" media="screen" rel="stylesheet" type="text/css" />     <link href="/stylesheets/jquery-ui-1.8.10.custom.css?1299691709" media="screen" rel="stylesheet" type="text/css" />     <link href="/stylesheets/screen.css?1299691709" media="screen" rel="stylesheet" type="text/css" />   </head>   <body id='home'>     <div id='contain'>       <div id='page'>         <!-- /home.html - home page for the application -->         <!-- /this is placed within the page div from the application.html.haml -->         <div id='headerHome'>           <div class='headline' id='headline'>             <div id='loginbox'>               <ul class='hmenu'>                 <li>                   <button id="create-user" type="button" name="signup" value="signup">Sign up</button>                 </li>                 <li>                   <button id="sign-in" type="button" name="signin" value="signin">Sign in</button>                 </li>               </ul>             </div> //and it goes on to render the entire markup of page

Even when I remove the datatype here:             dataType: 'json'

It still gives same error report.

Any idea as to whether this is devise related?

Thanks for response.

Has anyone gotten devise to work at all with any kind of ajax?