Grails sign up with Modal Window - grails

Question

I am using grails 2.1.1 and trying to sign up a new user with modal window. My signup modal window's .gsp code is as follows...
....
<!--Start of Registration Modal Page-->
<div id="register" class="modal hide fade" aria-labelledby="modalLabel" aria-hidden="true">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">
<i class="icon-remove"></i>
</button>
<h3 id="modalLabel">
Register
</h3>
</div>
<div class="modal-body">
<g:form method="POST">
<div class="controls controls-row">
<div class="span1"></div>
<input type="text" class="span2" placeholder="Full Name" value="${user?.profile?.fullName}">
<div class="span1"></div>
</div>
<div class="controls controls-row">
<div class="span1"></div>
<input type="text" class="span3" placeholder="Email" value="${user?.profile?.email}">
<div class="span1"></div>
</div>
<div class="controls controls-row">
<div class="span1"></div>
<input type="text" class="span3" placeholder="Username" value="${user?.username}">
<div class="span1"></div>
</div>
<div class="controls controls-row">
<div class="span1"></div>
<input type="password" class="span3" placeholder="Password" value="${user?.password}">
<div class="span1"></div>
</div>
<div class="controls controls-row">
<div class="span1"></div>
<input type="text" class="span3" placeholder="Bio" value="${user?.profile?.bio}">
<div class="span1"></div>
</div>
<div class="controls controls-row">
<div class="span1"></div>
<button type="submit" class="span3 btn btn-warning">Create Account</button>
<div class="span1"></div>
</div>
<div class="modal-footer">
<button class="btn btn-danger" data-dismiss="modal" aria-hidden="true">Cancel
</button>
<button class="btn btn-success" type="submit">Register
</button>
</div>
</div>
</div>
</g:form><!--End of Form-->
<!--End of Registration Modal Page-->
My corresponding controller is "user" and I have a customized "register" action there as well. All I want is that when I click Create Account button, the user is registered behind in the database. Is there any way to make it up through modal window form directly?