JQuery Div Clicks, Catching Undesirable Clicks?

To make divs clickable I use this:

$(".clickable").click(function (event) {
window.location = $(this).find('a').attr('href');
event.preventDefault();
});

I'm using an <asp:Repeater> in asp.NET to create several such <div>s.The problem is that all clicks in the div are picked up by this jQuery - I also have an <asp:Button> inside the div, for this I want to catch the click as normal and process it in the repeater_ItemCommand event - But this doesn't fire - the page just redirects to the href found in the hyperlink in the div.