Using Sitemesh, SWF 2.0

Problem: I have a tabbed component and I want to make an ajax call to load the data in a tab when selected. I figured it made sense to make each tab their own view-state. The problem is that in order to prevent Sitemesh from decorating the response, I need to include the request parameter 'requestType=ajax' in the url when fetching the view. When I transition to the new view-state, the request parameters are not used in the url, so Sitemesh incorrectly decorates the response.

How can I make it so Spring Web Flow includes the request parameter when rendering the view on transition?

Example:
Code:
  <view-state id="start" view="mainview">
    <transition on="tab1" to="tab1">
      <!-- this didn't work -->
      <set name="requestScope.requestType value="requestParameters.requestType" /> 
    </transition>
  </view-state>
  
  <view-state id="tab1" view="tabs/tab1" >