function createMarker(point, id, name, address, rooms_sale, rooms_rent ) {
	var marker = new GMarker(point);
	marker.value = id;

	GEvent.addListener(marker, "click", function() {
		console.log('You clicked on ID ' + id);
	});

	GEvent.addListener(marker, "mouseover", function() {
		var pointInfo = '<h2 style="margin: 0 0 .5em 0;">' + name + '</h2><p><strong>' + address + '</strong><br />' + rooms_sale + ' habitaciones de venta<br />' + rooms_rent + ' habitaciones de alquiler.</p>';
		marker.openInfoWindowHtml(pointInfo);
	});

	return marker;
}

http://groups.google.com/group/Google-Maps-API/browse_thread/thread/fd9c388fb2af590f/bf715966427ad869?lnk=gst&q=mouseover+click+event+problem#bf715966427ad869

simultaneous 'click' and 'mouseover' events on Google Maps marker

JavaScript