Can JQuery.Validate plugin prevent submission of an Ajax form
You need to add a callback function for use with the beforeSubmit event when initializing the ajaxForm():
var options = { beforeSubmit: function() { return $('#searchForm').validate().form(); }, target: '#detailsView' };
Now it knows to check the result of the validation before it will submit the page.
... well it's been a while so my situation has changed a little. Currently I have a submitHandler option passed to the Validate() plugin. In that handler I manually use ajaxSubmit. More a workaround than an answer I guess. Hope that helps.
http://jquery.bassistance.de/validate/demo/ajaxSubmit-intergration-demo.html
var v = jQuery("#form").validate({ submitHandler: function(form) { jQuery(form).ajaxSubmit({target: "#result"}); }});
$('#contactform').ajaxForm({ success : FormSendResponse, beforeSubmit: function(){ return $("#contactform").valid(); }});$("#contactform").validate();
Above code worked fine for me.