$(document).ready(function() { 
    var options = { 
        beforeSubmit:  validate,  // pre-submit callback 
        success:       showResponse  // post-submit callback 
    }; 
    $('#mindshareForm').ajaxForm(options);
}); 


// pre-submit callback 
function validate(formData, jqForm, options)
{ 
	var emailMindshareValue = $('input[name=emailMindshare]').fieldValue(); 

	if
	(!emailMindshareValue[0]) {
  		 $('#contactSubmitted').text('Please add your email address.');
		 return false;
		}
} 
 
// post-submit callback 
function showResponse(responseText, statusText)  {
   $('#mindshareForm').resetForm();
   $('#contactSubmitted').text('Thank you. We will add you to our mailing list.');
}