[devote]

ну дык это и называется костыль

<div id="la" style="width: 100px; height: 100px; background: #f00;">
    <a href="">test</a>
</div>
<script>
    function onMouseEnter( elem, callback ) {
        if ( "onmouseenter" in elem ) {
            if ( elem.addEventListener ) {
                 elem.addEventListener( "mouseenter", callback, false );
            } else {
                 elem.attachEvent( "onmouseenter", callback );
            }
        } else if ( elem.addEventListener ) {
            elem.addEventListener( 'mouseover', function( event ) {

                var relTarg = event.relatedTarget;

                while( relTarg && relTarg !== elem && ( relTarg = relTarg.parentNode ) ) {}

                if ( relTarg !== elem ) {
                    callback && callback.call( this, event );
                }
            }, false );
        }
    }

    function onMouseLeave( elem, callback ) {
        if ( "onmouseleave" in elem ) {
            if ( elem.addEventListener ) {
                 elem.addEventListener( "mouseleave", callback, false );
            } else {
                 elem.attachEvent( "onmouseleave", callback );
            }
        } else if ( elem.addEventListener ) {
            elem.addEventListener( 'mouseout', function( event ) {

                var relTarg = event.relatedTarget;

                while( relTarg && relTarg !== elem && ( relTarg = relTarg.parentNode ) ) {}

                if ( relTarg !== elem ) {
                    callback && callback.call( this, event );
                }
            }, false );
        }
    }

    var elem = document.getElementById('la');
    onMouseEnter( elem, function() {
        document.body.appendChild(document.createTextNode('over|'));
    });
    onMouseLeave( elem, function() {
        document.body.appendChild(document.createTextNode('out|'));
    });
</script>