function focus_datum_aanvang(obj)
{
	var datum_einde = elemById("datum_einde");
	objlng= elemById("lng");
	lng=objlng.value;
	if(isLessThanToday(obj)==false)
	{
		if(obj.value!="")
		alert(msg_START_DATE_IS_NOT_VALID);
		obj.value="";
		datum_einde.value="";
		return false;
	}
	datum_einde.value=obj.value;
}

function focus_datum_einde(obj)
{
	var datum_aanvang = elemById("datum_aanvang");
	objlng= elemById("lng");
	lng=objlng.value;
//	alert(datum_aanvang.value);
//	alert(isLessThanStartDate(datum_aanvang,obj));
	if(isLessThanStartDate(datum_aanvang,obj)==false)
	{
		if (obj.value != "") alert(msg_END_DATE_IS_NOT_VALID);
		obj.value=datum_aanvang.value;
		return false;
	}
}

function isLessThanStartDate(startDate,endDate)
{
	var retvalue=false;
	var sd=startDate.value.split("-");
	var ed=endDate.value.split("-");
	
	var startDate = new Date();
	var endDate = new Date();
	
	if(lng=="EN")
	{
		startDate = new Date(sd[2],sd[0]-1,(sd[1]),23,59,59);
		endDate = new Date(ed[2],ed[0]-1,(ed[1]),23,59,59);
	}
	else if(lng=="NL")
	{
		startDate = new Date(sd[2],sd[1]-1,sd[0],23,59,59);
		endDate = new Date(ed[2],ed[1]-1,ed[0],23,59,59);
//		alert(startDate);
//		alert(endDate);
	}
	if(startDate <= endDate)
	{
		retvalue=true;
	}
	return retvalue;
}