jQuery 1.4.1 now supports "hover" for live() events, but only with one event handler function:

$("table tr").live("hover",

function () {

});

Alternatively, you can provide two functions, one for mouseenter and one for mouseleave:

$("table tr").live({
    mouseenter: function () {

    },
    mouseleave: function () {

    }
});

$('.hoverme').live('mouseover mouseout', function(event) {
  if (event.type == 'mouseover') {
    // do something on mouseover
  } else {
    // do something on mouseout
  }
});

http://api.jquery.com/live/