I need to create a bootstrap accordion. The markup below works fine, but it does not auto-collapse the previously opened element. For example, open panel1, then click on panel2.. panel1 should then auto-close, but it does not. I have tried copying the markup exactly from the bootstrap site (http://twitter.github.com/bootstrap/javascript.html#collapse), but it is not working. What am I missing?

<h3>ACCORDION DEMO</h3>

<div class=accordion id=accordion1>

    <div class=accordion-group>

        <div class=accordion-heading>

            <a class=accordion-toggle data-parent=accordion1 data-toggle=collapse href=#panel1>Panel 1</a>

        </div>

        <div class=accordion-body collapse id=panel1>

            <div class=accordion-inner>

                <p>This is accordion panel 1 content</p>

            </div>

        </div>

    </div>

    <div class=accordion-group>

        <div class=accordion-heading>

            <a class=accordion-toggle data-parent=accordion1 data-toggle=collapse href=#panel2>Panel 2</a>

        </div>

        <div class=accordion-body collapse id=panel2>

            <div class=accordion-inner>

                <p>This is accordion panel 2 content</p>

            </div>

        </div>

    </div>

</div>