Here is an extension that delivers some missing parameters for the jQueryAccordion (i. e. not the extension but the integrated one):
http://www.mediafire.com/?ttho1zw7rqd121p
With this extension you will have the following choices:
active: false or # of tab If set to false the accordion will start closed, otherwise with the indicated tab (notice that it will start with 0 for the first tab) If set to false you can only use effect:click and not effect:mouseover
collapsible: true or false Gives you the possibility to close all tabs if set to true
For these two upper options you have to set the ID of the Accordion correctly in the extension!
font-weight: normal or bold
font-style: normal or italic