// JavaScript Document
function popUp(targ, itemW, itemH){

	// configura largura do popUp
	if(itemW == undefined){
		var itemW = (screen.availWidth)-(screen.availWidth/3);
	}else{
		var itemW = parseInt(itemW)+20;
	}
	
	// configura altura do popUp
	if(itemH == undefined){
		var itemH = (screen.availHeight)-(screen.availHeight/5);		
	}else{
		var itemH = parseInt(itemH)+20;
	}
	
	// configura centro da pagina
	var lX = (screen.availWidth/2)-(itemW/2);
	var hX = (screen.availHeight/2)-(itemH/2);
	
	// cria string de configurações
	var extra = 'width='+itemW+',height='+itemH+',left='+lX+',top='+hX+',resizable=1,scrollbars=yes';
	
	// abre popUp
	javascript:window.open(targ,'',extra);
};