[PPower4] accents in the slide title

[Frederico Moraes Ferreira]

Dear all,
I have experienced problems to put accents like \'a, \~a, etc in the slide titles. The 
accents in the body of the slide is working just fine.
A quick look in the ppower4 mailing archives retuned no sufficient explanations for
me to get around this (newbie). Please could anybody possibly help me?
Thanks in advance,
Fred

P.S.:my header goes,
\documentclass[20pt,landscape]{foils}
\usepackage{mdwslides}
\usepackage[english]{babel}
\usepackage{hyperref}
\hypersetup{
 pdfstartpage=1,
 pdfmenubar=true,
 pdftoolbar=true,
 pdfpagemode={None}
}
\usepackage{pause}
\usepackage{graphicx}
it has no difference on using the brazil-babel package.