Soucis d'accents

Bonjour,

Je suis en train modifier une page en php et j'ai un soucis, les accents apparaissent en "?" et je ne vois pas comment faire.

Voici le code (J'ai souligné l'élément avec l'accent, il y en a qu'un pour l'instant mais je compte en ajouter) :

<?php
global $colors;
?>
<html>
<head>
<title>VIF - Supervision clients SaaS - Cacti</title>
<link href="include/main.css" rel="stylesheet">
<link href="images/favicon.ico" rel="shortcut icon" type="image/x-icon" />
<script type="text/javascript" src="include/layout.js"></script>
<?php if (isset($refresh)) {
print "<meta http-equiv=refresh content=\"" . $refresh["seconds"] . "; url='" . $refresh["page"] . "'\">";
}?>
</style>
</head>

<body leftmargin="0" topmargin="0" marginwidth="0" marginheight="0" background="images/left_border.gif">

<table width="100%" cellspacing="0" cellpadding="0">
<tr height="1" bgcolor="#FFFFFF">
<td valign="bottom" colspan="3" nowrap>
<table width="100%" cellspacing="0" cellpadding="0">
<tr height="100" style="background: transparent url('images/cacti_backdrop2.gif') no-repeat center left;">
<td id="tabs" valign="bottom">
 <a href="index.php"><img src="images/tab_console_down.gif" alt="Console" align="absmiddle" border="0"></a><a href="graph_view.php"><img src="images/tab_graphs.gif" alt="Graphs" align="absmiddle" border="0"></a>
</td>
</tr>
</table>
</td>
</tr>
<tr height="2" bgcolor="#183c8f">
<td colspan="3">
<img src="images/transparent_line.gif" height="2" border="0"><br>
</td>
</tr>
<tr height="5" bgcolor="#e9e9e9">
<td colspan="3">
<table width="100%">
<tr>
<td>
<?php draw_navigation_text();?>
</td>
<td align="right">
<?php if (read_config_option("auth_method") != 0) { ?>
Utilisateur : <strong><?php print db_fetch_cell("select username from user_auth where id=" . $_SESSION["sess_user_id"]);?></strong> (<a href="logout.php">Déconnexion</a>) 
<?php } ?>
</td>
</tr>
</table>
</td>
</tr>
<tr>
<td bgcolor="#f5f5f5" colspan="1" height="8" width="135" style="background-image: url(images/shadow_gray.gif); background-repeat: repeat-x; border-right: #aaaaaa 1px solid;">
<img src="images/transparent_line.gif" width="135" height="2" border="0"><br>
</td>
<td colspan="2" height="8" style="background-image: url(images/shadow.gif); background-repeat: repeat-x;" bgcolor="#ffffff">

</td>
</tr>
<tr>
<td valign="top" colspan="1" rowspan="2" width="135" style="padding: 5px; border-right: #aaaaaa 1px solid;" bgcolor='#f5f5f5'>
<table bgcolor="#f5f5f5" width="100%" cellpadding="1" cellspacing="0" border="0">
<?php draw_menu();?>
</table>

<img src="images/transparent_line.gif" width="135" height="5" border="0"><br>
<p align="center"><a href='about.php'><img src="images/cacti_logo.gif" border="0"></a></p>
<img src="images/transparent_line.gif" width="135" height="5" border="0"><br>
</td>
<td width="100%" colspan="2" valign="top" style="padding: 5px; border-right: #aaaaaa 1px solid;"><?php display_output_messages();?>

Merci pour votre aide !