function abrirPopup(arquivo, largura, altura, pScroll)
{
	alturaTela = (screen != null ? screen.availHeight : 600);
	larguraTela = (screen != null ? screen.availWidth : 800);
	
	ntop = (alturaTela - altura) / 2;
	nleft = (larguraTela - largura) / 2;

	window.open(arquivo, 'popup_' + (new Date()).getSeconds(), 'width=' + largura + ',height=' + altura + ',status=no,menubar=no,locationbar=no,top=' + ntop + ',left=' + nleft + (pScroll == true ? ',scrollbars=yes' : ''));
}