nima,
the box is made with mktree.js + mktree.css (actually, a already more dense presentation, provided in /resources/xowiki/cattree.css).
mktree is used on several places in openacs. feel free to make a suggestion for a better style file. i have no experience, how wrapping in lists can be addressed with css.
i just tried openacs.org with IE, and saw indeed a larger space on top and bottom of an opened item. However, at least with IE 6.0, the plus and minus signs are displayed correctly. what version of IE do you have?
Concerning the javascript error message when opening xinha. As far i can tell, this happens only on oacs.org. we have several installations of openacs with german localization, this message shows nowhere up. interesting enough, the file where it complains about a syntax error, does not exist.
