Try this.
<div id="c1" class="easyui-calendar" style="width:250px;height:250px;"></div>
.calendar-other-month{
visibility: hidden;
}
$('#c1').calendar({
onNavigate: function(year,month){
if($("#c1").find("tr.calendar-first").find(".calendar-last").css("visibility") == 'hidden'){
$("#c1").find("tr.calendar-first").css("display","none");
}
if($("#c1").find("tr.calendar-last").find(".calendar-first").css("visibility") == 'hidden'){
$("#c1").find("tr.calendar-last").css("display","none");
}
}
});
http://code.reloado.com/jbhatti/24/edit