Thanks for your reply!
I am trying to implement the menu on a Drupal installation.
Everything seems to work well except for the your are here extentions, which generates the previously mentioned error.
I see that you commented out all of those javascript lines. Try adding them back in one by one starting with the /misc/jquery.js line. At what point do you start seeing the error? That should identify the problem script out of the 5 or 6 that you have.
Thanks for your suggestion, but I have tried that already.
The error is caused by the first call:
<script type="text/javascript" src="/misc/jquery.js"></script>
I disabled the other scripts as well because they use the jquery library and they will generate a lot of errors if the jquery.js is not included.