radio button not working properly, list is sorted for every two clicks

[tej ku]

Hi,
I am trying to use a radio button for ascending and descending a list of items but the list is sorted if we click two times radio button
(1 click descending radio button and second click ascending radio button now descended item list are displayed.)

<tr>
<td colspan="3">
<h:panelGrid columns="6" cellpadding="0" cellspacing="0">
<hutputLabel escape="false" styleClass="label" value="Sort By: " for="sortBy" />
<h:selectOneMenu id="sortBy" value="#{decFilter.sortBy}">
<f:selectItems value="#{decInProgressAction.orderByList}" />
<a:support event="onchange" action="#{decInProgressAction.doFiltering}"
reRender="mainForm" ignoreDupResponses="true" eventsQueue="default" />
</h:selectOneMenu>
<h:selectOneRadio value="#{decFilter.ascDesc}">
<f:selectItems value="#{decInProgressAction.orderByAscDescList}" />
<a:support event="onchange" action="#{decInProgressAction.doFiltering}"
reRender="mainForm" ignoreDupResponses="true" eventsQueue="default" />
</h:selectOneRadio>
</h:panelGrid>
</td>
</tr>

[tej ku]

I just found it is working fine in FIREFOX not in internet explorer..........