it can be done with a4j:jsFunction :
<f:selectItem itemLabel="1" itemValue="1"/>
<f:selectItem itemLabel="2" itemValue="2"/>
<a4j:ajax event="change" execute="@this" oncomplete="navigate()"/>
<a4j:jsFunction name="navigate" action="yourNavigation rule"/>
Thanks a lot Ibrahim.
It worked for me. but i have another problem. I have used your solution in a page. Same page has a4j:poll. When the poll is happening if I select the drop down its not calling the action method configured in a4j:jsfunction. But when the poll stops or poll is disabled it works. Does a4j:poll block other a4j requests. ( They are in diffferent forms). Do I have to use @execute in poll ? or Do ihave to use a4j:region ?
honestly i didn't try this, could you please check @execute, a4j:region and reply back.
I tried execute=''@none" it worked.