I am using a jQuery UI Dialog to pop-up some supplementary information on one of my pages. For some reason, in Chrome 11 and Firefox 4, the titlebar is ridiculously tall. For
I don't know if it makes a difference, but you could try using a title attribute directly on your div instead of setting it in code:
It could be that you have a cascading style issue. I use Chrome's developer tools to track these kinds of issues down. You can isolate the title element generated by jQuery-ui and examine the classes that it has inherited.