Paging issues with rich:dataScroller and dynamic row count

Issue

Wrong number of rows is displayed when using rich:dataTable with dynamic rowCount.
Example:

<h:selectOneMenu value="#{myBean.batchRows}">
   <f:selectItem itemLabel="10" itemValue="10"/>
   <f:selectItem itemLabel="20" itemValue="20"/>
   <f:ajax render="table table-ds" />
</h:selectOneMenu>
<h:panelGroup>
   <rich:dataTable id="table" rows="#{myBean.batchRows}" ... >
   ...
   </rich:dataTable>
</h:panelGroup>

<rich:dataScroller id="table-ds" for="table"/>

Behaviour with 21 elements
1. Choose 20 from the menu input.
2. 20 elements will be displayed
3. Go to page 2, 1 element is displayed
4. Choose 10 from the menu input.
5. Just one element is still displayed, but 10 should be displayed.