[jQuery] custom selecters

Hi, i need to be able to find all elements with a div id of something
like divname plus some randmom number, each div id will be like this,
so something like divname324 or divname453
so how can I select all divs with a name divname plus some random
numbers
$("#divname + random number").ajaxForm({
target: '#commentFormOutput',
success: processcommentForm
});
Thanks
-TJ