When a tooltip containing Devanagari text is displayed, it is too tall and has a large amount of space between the bottom of the text and the bottom edge of the tooltip box. To reproduce, mouse over one of the links in the above URL.
Screenshot: http://mcc.id.au/temp/2008/devanagari-tooltip.png
Created attachment 23394 [details] test case
I'm not quite sure, but I think that tooltips are a Safari feature, and not in WebKit.