Sounds like they are building an option for this. In qTip2 you would use hide: {fixed: true}. I am guessing they will do something similar here. In the meantime this code worked for me.
$( "[title]" )
.bind( "mouseleave", function( event ) {
event.stopImmediatePropagation();
var fixed = setTimeout('$("[title]").tooltip("close")', 500);
$(".ui-tooltip").hover(
function(){clearTimeout (fixed);},
function(){$("[title]").tooltip("close");}
);
})
.tooltip();