I am stuck with this problem too.
I have tried everything suggested on http://wordpress.org/support/topic/my-link-to-an-accordion-doesnt-open-it?replies=17 and http://kav.in/projects/blog/linking-to-tabs-accordions-and-spoilers-in-wp-ui/ as well as other support threads with users having exactly the same issue. To me, motorhobo's explanation on the 1st link just given sounds plausible to me, but it doesn't seem that there´s been any feedback since as to the fixing of this possible bug.
My accordion is over at: http://kunden.paulvetter.de/hertzer/hertzer/
I have no jQuery Errors in my console. I have used Firebug to make sure I am using the correct ID for the hashtag anchor, etc.
I have also tried using the CDN.
The only other plugin I use is the Slider PRO for WordPress.
But then the example at http://kav.in/projects/blog/linking-to-tabs-accordions-and-spoilers-in-wp-ui/#lorem does NOT work either, so it can't be anything to do with my local installation, but it's something that's wrong with the plugin to start with.
Thank you for any help and I hope you can eradicate this bug, as I would otherwise have to move to another plugin that supports this feature.
All the best